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![Rayagonda Kokatanur](/assets/img/avatar_default.png)
Add code to handle IS_S_RX_FIFO_FULL_SHIFT interrupt to support master write request with >= 64 bytes. Iproc has a slave rx fifo size of 64 bytes. Rx fifo full interrupt (IS_S_RX_FIFO_FULL_SHIFT) will be generated when RX fifo becomes full. This can happen if master issues write request of more than 64 bytes. Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur@broadcom.com> Acked-by: Ray Jui <ray.jui@broadcom.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
1279 lines
36 KiB
C
1279 lines
36 KiB
C
/*
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* Copyright (C) 2014 Broadcom Corporation
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation version 2.
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*
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* This program is distributed "as is" WITHOUT ANY WARRANTY of any
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* kind, whether express or implied; without even the implied warranty
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* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*/
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#include <linux/delay.h>
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#include <linux/i2c.h>
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#include <linux/interrupt.h>
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#include <linux/io.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/of_device.h>
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#include <linux/platform_device.h>
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#include <linux/slab.h>
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#define IDM_CTRL_DIRECT_OFFSET 0x00
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#define CFG_OFFSET 0x00
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#define CFG_RESET_SHIFT 31
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#define CFG_EN_SHIFT 30
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#define CFG_SLAVE_ADDR_0_SHIFT 28
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#define CFG_M_RETRY_CNT_SHIFT 16
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#define CFG_M_RETRY_CNT_MASK 0x0f
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#define TIM_CFG_OFFSET 0x04
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#define TIM_CFG_MODE_400_SHIFT 31
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#define TIM_RAND_SLAVE_STRETCH_SHIFT 24
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#define TIM_RAND_SLAVE_STRETCH_MASK 0x7f
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#define TIM_PERIODIC_SLAVE_STRETCH_SHIFT 16
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#define TIM_PERIODIC_SLAVE_STRETCH_MASK 0x7f
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#define S_CFG_SMBUS_ADDR_OFFSET 0x08
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#define S_CFG_EN_NIC_SMB_ADDR3_SHIFT 31
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#define S_CFG_NIC_SMB_ADDR3_SHIFT 24
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#define S_CFG_NIC_SMB_ADDR3_MASK 0x7f
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#define S_CFG_EN_NIC_SMB_ADDR2_SHIFT 23
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#define S_CFG_NIC_SMB_ADDR2_SHIFT 16
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#define S_CFG_NIC_SMB_ADDR2_MASK 0x7f
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#define S_CFG_EN_NIC_SMB_ADDR1_SHIFT 15
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#define S_CFG_NIC_SMB_ADDR1_SHIFT 8
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#define S_CFG_NIC_SMB_ADDR1_MASK 0x7f
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#define S_CFG_EN_NIC_SMB_ADDR0_SHIFT 7
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#define S_CFG_NIC_SMB_ADDR0_SHIFT 0
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#define S_CFG_NIC_SMB_ADDR0_MASK 0x7f
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#define M_FIFO_CTRL_OFFSET 0x0c
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#define M_FIFO_RX_FLUSH_SHIFT 31
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#define M_FIFO_TX_FLUSH_SHIFT 30
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#define M_FIFO_RX_CNT_SHIFT 16
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#define M_FIFO_RX_CNT_MASK 0x7f
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#define M_FIFO_RX_THLD_SHIFT 8
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#define M_FIFO_RX_THLD_MASK 0x3f
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#define S_FIFO_CTRL_OFFSET 0x10
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#define S_FIFO_RX_FLUSH_SHIFT 31
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#define S_FIFO_TX_FLUSH_SHIFT 30
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#define S_FIFO_RX_CNT_SHIFT 16
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#define S_FIFO_RX_CNT_MASK 0x7f
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#define S_FIFO_RX_THLD_SHIFT 8
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#define S_FIFO_RX_THLD_MASK 0x3f
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#define M_CMD_OFFSET 0x30
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#define M_CMD_START_BUSY_SHIFT 31
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#define M_CMD_STATUS_SHIFT 25
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#define M_CMD_STATUS_MASK 0x07
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#define M_CMD_STATUS_SUCCESS 0x0
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#define M_CMD_STATUS_LOST_ARB 0x1
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#define M_CMD_STATUS_NACK_ADDR 0x2
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#define M_CMD_STATUS_NACK_DATA 0x3
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#define M_CMD_STATUS_TIMEOUT 0x4
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#define M_CMD_STATUS_FIFO_UNDERRUN 0x5
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#define M_CMD_STATUS_RX_FIFO_FULL 0x6
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#define M_CMD_PROTOCOL_SHIFT 9
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#define M_CMD_PROTOCOL_MASK 0xf
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#define M_CMD_PROTOCOL_QUICK 0x0
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#define M_CMD_PROTOCOL_BLK_WR 0x7
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#define M_CMD_PROTOCOL_BLK_RD 0x8
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#define M_CMD_PROTOCOL_PROCESS 0xa
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#define M_CMD_PEC_SHIFT 8
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#define M_CMD_RD_CNT_SHIFT 0
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#define M_CMD_RD_CNT_MASK 0xff
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#define S_CMD_OFFSET 0x34
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#define S_CMD_START_BUSY_SHIFT 31
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#define S_CMD_STATUS_SHIFT 23
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#define S_CMD_STATUS_MASK 0x07
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#define S_CMD_STATUS_SUCCESS 0x0
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#define S_CMD_STATUS_TIMEOUT 0x5
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#define S_CMD_STATUS_MASTER_ABORT 0x7
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#define IE_OFFSET 0x38
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#define IE_M_RX_FIFO_FULL_SHIFT 31
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#define IE_M_RX_THLD_SHIFT 30
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#define IE_M_START_BUSY_SHIFT 28
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#define IE_M_TX_UNDERRUN_SHIFT 27
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#define IE_S_RX_FIFO_FULL_SHIFT 26
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#define IE_S_RX_THLD_SHIFT 25
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#define IE_S_RX_EVENT_SHIFT 24
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#define IE_S_START_BUSY_SHIFT 23
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#define IE_S_TX_UNDERRUN_SHIFT 22
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#define IE_S_RD_EVENT_SHIFT 21
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#define IS_OFFSET 0x3c
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#define IS_M_RX_FIFO_FULL_SHIFT 31
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#define IS_M_RX_THLD_SHIFT 30
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#define IS_M_START_BUSY_SHIFT 28
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#define IS_M_TX_UNDERRUN_SHIFT 27
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#define IS_S_RX_FIFO_FULL_SHIFT 26
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#define IS_S_RX_THLD_SHIFT 25
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#define IS_S_RX_EVENT_SHIFT 24
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#define IS_S_START_BUSY_SHIFT 23
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#define IS_S_TX_UNDERRUN_SHIFT 22
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#define IS_S_RD_EVENT_SHIFT 21
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#define M_TX_OFFSET 0x40
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#define M_TX_WR_STATUS_SHIFT 31
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#define M_TX_DATA_SHIFT 0
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#define M_TX_DATA_MASK 0xff
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#define M_RX_OFFSET 0x44
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#define M_RX_STATUS_SHIFT 30
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#define M_RX_STATUS_MASK 0x03
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#define M_RX_PEC_ERR_SHIFT 29
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#define M_RX_DATA_SHIFT 0
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#define M_RX_DATA_MASK 0xff
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#define S_TX_OFFSET 0x48
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#define S_TX_WR_STATUS_SHIFT 31
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#define S_TX_DATA_SHIFT 0
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#define S_TX_DATA_MASK 0xff
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#define S_RX_OFFSET 0x4c
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#define S_RX_STATUS_SHIFT 30
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#define S_RX_STATUS_MASK 0x03
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#define S_RX_PEC_ERR_SHIFT 29
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#define S_RX_DATA_SHIFT 0
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#define S_RX_DATA_MASK 0xff
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#define I2C_TIMEOUT_MSEC 50000
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#define M_TX_RX_FIFO_SIZE 64
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#define M_RX_FIFO_MAX_THLD_VALUE (M_TX_RX_FIFO_SIZE - 1)
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#define M_RX_MAX_READ_LEN 255
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#define M_RX_FIFO_THLD_VALUE 50
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#define IE_M_ALL_INTERRUPT_SHIFT 27
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#define IE_M_ALL_INTERRUPT_MASK 0x1e
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#define SLAVE_READ_WRITE_BIT_MASK 0x1
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#define SLAVE_READ_WRITE_BIT_SHIFT 0x1
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#define SLAVE_MAX_SIZE_TRANSACTION 64
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#define SLAVE_CLOCK_STRETCH_TIME 25
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#define IE_S_ALL_INTERRUPT_SHIFT 21
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#define IE_S_ALL_INTERRUPT_MASK 0x3f
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/*
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* It takes ~18us to reading 10bytes of data, hence to keep tasklet
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* running for less time, max slave read per tasklet is set to 10 bytes.
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*/
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#define MAX_SLAVE_RX_PER_INT 10
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enum i2c_slave_read_status {
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I2C_SLAVE_RX_FIFO_EMPTY = 0,
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I2C_SLAVE_RX_START,
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I2C_SLAVE_RX_DATA,
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I2C_SLAVE_RX_END,
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};
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enum bus_speed_index {
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I2C_SPD_100K = 0,
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I2C_SPD_400K,
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};
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enum bcm_iproc_i2c_type {
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IPROC_I2C,
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IPROC_I2C_NIC
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};
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struct bcm_iproc_i2c_dev {
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struct device *device;
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enum bcm_iproc_i2c_type type;
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int irq;
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void __iomem *base;
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void __iomem *idm_base;
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u32 ape_addr_mask;
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/* lock for indirect access through IDM */
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spinlock_t idm_lock;
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struct i2c_adapter adapter;
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unsigned int bus_speed;
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struct completion done;
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int xfer_is_done;
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struct i2c_msg *msg;
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struct i2c_client *slave;
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/* bytes that have been transferred */
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unsigned int tx_bytes;
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/* bytes that have been read */
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unsigned int rx_bytes;
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unsigned int thld_bytes;
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bool slave_rx_only;
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bool rx_start_rcvd;
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bool slave_read_complete;
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u32 tx_underrun;
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u32 slave_int_mask;
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struct tasklet_struct slave_rx_tasklet;
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};
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/* tasklet to process slave rx data */
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static void slave_rx_tasklet_fn(unsigned long);
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/*
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* Can be expanded in the future if more interrupt status bits are utilized
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*/
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#define ISR_MASK (BIT(IS_M_START_BUSY_SHIFT) | BIT(IS_M_TX_UNDERRUN_SHIFT)\
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| BIT(IS_M_RX_THLD_SHIFT))
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#define ISR_MASK_SLAVE (BIT(IS_S_START_BUSY_SHIFT)\
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| BIT(IS_S_RX_EVENT_SHIFT) | BIT(IS_S_RD_EVENT_SHIFT)\
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| BIT(IS_S_TX_UNDERRUN_SHIFT) | BIT(IS_S_RX_FIFO_FULL_SHIFT)\
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| BIT(IS_S_RX_THLD_SHIFT))
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static int bcm_iproc_i2c_reg_slave(struct i2c_client *slave);
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static int bcm_iproc_i2c_unreg_slave(struct i2c_client *slave);
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static void bcm_iproc_i2c_enable_disable(struct bcm_iproc_i2c_dev *iproc_i2c,
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bool enable);
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static inline u32 iproc_i2c_rd_reg(struct bcm_iproc_i2c_dev *iproc_i2c,
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u32 offset)
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{
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u32 val;
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if (iproc_i2c->idm_base) {
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spin_lock(&iproc_i2c->idm_lock);
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writel(iproc_i2c->ape_addr_mask,
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iproc_i2c->idm_base + IDM_CTRL_DIRECT_OFFSET);
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val = readl(iproc_i2c->base + offset);
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spin_unlock(&iproc_i2c->idm_lock);
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} else {
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val = readl(iproc_i2c->base + offset);
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}
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return val;
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}
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static inline void iproc_i2c_wr_reg(struct bcm_iproc_i2c_dev *iproc_i2c,
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u32 offset, u32 val)
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{
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if (iproc_i2c->idm_base) {
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spin_lock(&iproc_i2c->idm_lock);
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writel(iproc_i2c->ape_addr_mask,
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iproc_i2c->idm_base + IDM_CTRL_DIRECT_OFFSET);
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writel(val, iproc_i2c->base + offset);
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spin_unlock(&iproc_i2c->idm_lock);
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} else {
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writel(val, iproc_i2c->base + offset);
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}
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}
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static void bcm_iproc_i2c_slave_init(
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struct bcm_iproc_i2c_dev *iproc_i2c, bool need_reset)
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{
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u32 val;
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iproc_i2c->tx_underrun = 0;
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if (need_reset) {
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/* put controller in reset */
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val = iproc_i2c_rd_reg(iproc_i2c, CFG_OFFSET);
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val |= BIT(CFG_RESET_SHIFT);
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iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);
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/* wait 100 usec per spec */
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udelay(100);
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/* bring controller out of reset */
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val &= ~(BIT(CFG_RESET_SHIFT));
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iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);
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}
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/* flush TX/RX FIFOs */
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val = (BIT(S_FIFO_RX_FLUSH_SHIFT) | BIT(S_FIFO_TX_FLUSH_SHIFT));
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iproc_i2c_wr_reg(iproc_i2c, S_FIFO_CTRL_OFFSET, val);
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/* Maximum slave stretch time */
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val = iproc_i2c_rd_reg(iproc_i2c, TIM_CFG_OFFSET);
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val &= ~(TIM_RAND_SLAVE_STRETCH_MASK << TIM_RAND_SLAVE_STRETCH_SHIFT);
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val |= (SLAVE_CLOCK_STRETCH_TIME << TIM_RAND_SLAVE_STRETCH_SHIFT);
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iproc_i2c_wr_reg(iproc_i2c, TIM_CFG_OFFSET, val);
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/* Configure the slave address */
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val = iproc_i2c_rd_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET);
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val |= BIT(S_CFG_EN_NIC_SMB_ADDR3_SHIFT);
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val &= ~(S_CFG_NIC_SMB_ADDR3_MASK << S_CFG_NIC_SMB_ADDR3_SHIFT);
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val |= (iproc_i2c->slave->addr << S_CFG_NIC_SMB_ADDR3_SHIFT);
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iproc_i2c_wr_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET, val);
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/* clear all pending slave interrupts */
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iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, ISR_MASK_SLAVE);
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/* Enable interrupt register to indicate a valid byte in receive fifo */
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val = BIT(IE_S_RX_EVENT_SHIFT);
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/* Enable interrupt register to indicate Slave Rx FIFO Full */
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val |= BIT(IE_S_RX_FIFO_FULL_SHIFT);
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/* Enable interrupt register to indicate a Master read transaction */
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val |= BIT(IE_S_RD_EVENT_SHIFT);
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/* Enable interrupt register for the Slave BUSY command */
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val |= BIT(IE_S_START_BUSY_SHIFT);
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iproc_i2c->slave_int_mask = val;
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iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val);
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}
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static void bcm_iproc_i2c_check_slave_status(
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struct bcm_iproc_i2c_dev *iproc_i2c)
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{
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u32 val;
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val = iproc_i2c_rd_reg(iproc_i2c, S_CMD_OFFSET);
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/* status is valid only when START_BUSY is cleared after it was set */
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if (val & BIT(S_CMD_START_BUSY_SHIFT))
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return;
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val = (val >> S_CMD_STATUS_SHIFT) & S_CMD_STATUS_MASK;
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if (val == S_CMD_STATUS_TIMEOUT || val == S_CMD_STATUS_MASTER_ABORT) {
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dev_err(iproc_i2c->device, (val == S_CMD_STATUS_TIMEOUT) ?
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"slave random stretch time timeout\n" :
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"Master aborted read transaction\n");
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/* re-initialize i2c for recovery */
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bcm_iproc_i2c_enable_disable(iproc_i2c, false);
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bcm_iproc_i2c_slave_init(iproc_i2c, true);
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bcm_iproc_i2c_enable_disable(iproc_i2c, true);
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}
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}
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static void bcm_iproc_i2c_slave_read(struct bcm_iproc_i2c_dev *iproc_i2c)
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{
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u8 rx_data, rx_status;
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u32 rx_bytes = 0;
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u32 val;
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while (rx_bytes < MAX_SLAVE_RX_PER_INT) {
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val = iproc_i2c_rd_reg(iproc_i2c, S_RX_OFFSET);
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rx_status = (val >> S_RX_STATUS_SHIFT) & S_RX_STATUS_MASK;
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rx_data = ((val >> S_RX_DATA_SHIFT) & S_RX_DATA_MASK);
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if (rx_status == I2C_SLAVE_RX_START) {
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/* Start of SMBUS Master write */
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i2c_slave_event(iproc_i2c->slave,
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I2C_SLAVE_WRITE_REQUESTED, &rx_data);
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iproc_i2c->rx_start_rcvd = true;
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iproc_i2c->slave_read_complete = false;
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} else if (rx_status == I2C_SLAVE_RX_DATA &&
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iproc_i2c->rx_start_rcvd) {
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/* Middle of SMBUS Master write */
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i2c_slave_event(iproc_i2c->slave,
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I2C_SLAVE_WRITE_RECEIVED, &rx_data);
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} else if (rx_status == I2C_SLAVE_RX_END &&
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iproc_i2c->rx_start_rcvd) {
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/* End of SMBUS Master write */
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if (iproc_i2c->slave_rx_only)
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i2c_slave_event(iproc_i2c->slave,
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I2C_SLAVE_WRITE_RECEIVED,
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&rx_data);
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i2c_slave_event(iproc_i2c->slave, I2C_SLAVE_STOP,
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&rx_data);
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} else if (rx_status == I2C_SLAVE_RX_FIFO_EMPTY) {
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iproc_i2c->rx_start_rcvd = false;
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iproc_i2c->slave_read_complete = true;
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break;
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}
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rx_bytes++;
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}
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}
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static void slave_rx_tasklet_fn(unsigned long data)
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{
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struct bcm_iproc_i2c_dev *iproc_i2c = (struct bcm_iproc_i2c_dev *)data;
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u32 int_clr;
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bcm_iproc_i2c_slave_read(iproc_i2c);
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/* clear pending IS_S_RX_EVENT_SHIFT interrupt */
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int_clr = BIT(IS_S_RX_EVENT_SHIFT);
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if (!iproc_i2c->slave_rx_only && iproc_i2c->slave_read_complete) {
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/*
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* In case of single byte master-read request,
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* IS_S_TX_UNDERRUN_SHIFT event is generated before
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* IS_S_START_BUSY_SHIFT event. Hence start slave data send
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* from first IS_S_TX_UNDERRUN_SHIFT event.
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*
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* This means don't send any data from slave when
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* IS_S_RD_EVENT_SHIFT event is generated else it will increment
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* eeprom or other backend slave driver read pointer twice.
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*/
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iproc_i2c->tx_underrun = 0;
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iproc_i2c->slave_int_mask |= BIT(IE_S_TX_UNDERRUN_SHIFT);
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/* clear IS_S_RD_EVENT_SHIFT interrupt */
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int_clr |= BIT(IS_S_RD_EVENT_SHIFT);
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}
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/* clear slave interrupt */
|
|
iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, int_clr);
|
|
/* enable slave interrupts */
|
|
iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, iproc_i2c->slave_int_mask);
|
|
}
|
|
|
|
static bool bcm_iproc_i2c_slave_isr(struct bcm_iproc_i2c_dev *iproc_i2c,
|
|
u32 status)
|
|
{
|
|
u32 val;
|
|
u8 value;
|
|
|
|
/*
|
|
* Slave events in case of master-write, master-write-read and,
|
|
* master-read
|
|
*
|
|
* Master-write : only IS_S_RX_EVENT_SHIFT event
|
|
* Master-write-read: both IS_S_RX_EVENT_SHIFT and IS_S_RD_EVENT_SHIFT
|
|
* events
|
|
* Master-read : both IS_S_RX_EVENT_SHIFT and IS_S_RD_EVENT_SHIFT
|
|
* events or only IS_S_RD_EVENT_SHIFT
|
|
*
|
|
* iproc has a slave rx fifo size of 64 bytes. Rx fifo full interrupt
|
|
* (IS_S_RX_FIFO_FULL_SHIFT) will be generated when RX fifo becomes
|
|
* full. This can happen if Master issues write requests of more than
|
|
* 64 bytes.
|
|
*/
|
|
if (status & BIT(IS_S_RX_EVENT_SHIFT) ||
|
|
status & BIT(IS_S_RD_EVENT_SHIFT) ||
|
|
status & BIT(IS_S_RX_FIFO_FULL_SHIFT)) {
|
|
/* disable slave interrupts */
|
|
val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
|
|
val &= ~iproc_i2c->slave_int_mask;
|
|
iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val);
|
|
|
|
if (status & BIT(IS_S_RD_EVENT_SHIFT))
|
|
/* Master-write-read request */
|
|
iproc_i2c->slave_rx_only = false;
|
|
else
|
|
/* Master-write request only */
|
|
iproc_i2c->slave_rx_only = true;
|
|
|
|
/* schedule tasklet to read data later */
|
|
tasklet_schedule(&iproc_i2c->slave_rx_tasklet);
|
|
|
|
/*
|
|
* clear only IS_S_RX_EVENT_SHIFT and
|
|
* IS_S_RX_FIFO_FULL_SHIFT interrupt.
|
|
*/
|
|
val = BIT(IS_S_RX_EVENT_SHIFT);
|
|
if (status & BIT(IS_S_RX_FIFO_FULL_SHIFT))
|
|
val |= BIT(IS_S_RX_FIFO_FULL_SHIFT);
|
|
iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, val);
|
|
}
|
|
|
|
if (status & BIT(IS_S_TX_UNDERRUN_SHIFT)) {
|
|
iproc_i2c->tx_underrun++;
|
|
if (iproc_i2c->tx_underrun == 1)
|
|
/* Start of SMBUS for Master Read */
|
|
i2c_slave_event(iproc_i2c->slave,
|
|
I2C_SLAVE_READ_REQUESTED,
|
|
&value);
|
|
else
|
|
/* Master read other than start */
|
|
i2c_slave_event(iproc_i2c->slave,
|
|
I2C_SLAVE_READ_PROCESSED,
|
|
&value);
|
|
|
|
iproc_i2c_wr_reg(iproc_i2c, S_TX_OFFSET, value);
|
|
/* start transfer */
|
|
val = BIT(S_CMD_START_BUSY_SHIFT);
|
|
iproc_i2c_wr_reg(iproc_i2c, S_CMD_OFFSET, val);
|
|
|
|
/* clear interrupt */
|
|
iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET,
|
|
BIT(IS_S_TX_UNDERRUN_SHIFT));
|
|
}
|
|
|
|
/* Stop received from master in case of master read transaction */
|
|
if (status & BIT(IS_S_START_BUSY_SHIFT)) {
|
|
/*
|
|
* Disable interrupt for TX FIFO becomes empty and
|
|
* less than PKT_LENGTH bytes were output on the SMBUS
|
|
*/
|
|
iproc_i2c->slave_int_mask &= ~BIT(IE_S_TX_UNDERRUN_SHIFT);
|
|
iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET,
|
|
iproc_i2c->slave_int_mask);
|
|
|
|
/* End of SMBUS for Master Read */
|
|
val = BIT(S_TX_WR_STATUS_SHIFT);
|
|
iproc_i2c_wr_reg(iproc_i2c, S_TX_OFFSET, val);
|
|
|
|
val = BIT(S_CMD_START_BUSY_SHIFT);
|
|
iproc_i2c_wr_reg(iproc_i2c, S_CMD_OFFSET, val);
|
|
|
|
/* flush TX FIFOs */
|
|
val = iproc_i2c_rd_reg(iproc_i2c, S_FIFO_CTRL_OFFSET);
|
|
val |= (BIT(S_FIFO_TX_FLUSH_SHIFT));
|
|
iproc_i2c_wr_reg(iproc_i2c, S_FIFO_CTRL_OFFSET, val);
|
|
|
|
i2c_slave_event(iproc_i2c->slave, I2C_SLAVE_STOP, &value);
|
|
|
|
/* clear interrupt */
|
|
iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET,
|
|
BIT(IS_S_START_BUSY_SHIFT));
|
|
}
|
|
|
|
/* check slave transmit status only if slave is transmitting */
|
|
if (!iproc_i2c->slave_rx_only)
|
|
bcm_iproc_i2c_check_slave_status(iproc_i2c);
|
|
|
|
return true;
|
|
}
|
|
|
|
static void bcm_iproc_i2c_read_valid_bytes(struct bcm_iproc_i2c_dev *iproc_i2c)
|
|
{
|
|
struct i2c_msg *msg = iproc_i2c->msg;
|
|
uint32_t val;
|
|
|
|
/* Read valid data from RX FIFO */
|
|
while (iproc_i2c->rx_bytes < msg->len) {
|
|
val = iproc_i2c_rd_reg(iproc_i2c, M_RX_OFFSET);
|
|
|
|
/* rx fifo empty */
|
|
if (!((val >> M_RX_STATUS_SHIFT) & M_RX_STATUS_MASK))
|
|
break;
|
|
|
|
msg->buf[iproc_i2c->rx_bytes] =
|
|
(val >> M_RX_DATA_SHIFT) & M_RX_DATA_MASK;
|
|
iproc_i2c->rx_bytes++;
|
|
}
|
|
}
|
|
|
|
static void bcm_iproc_i2c_send(struct bcm_iproc_i2c_dev *iproc_i2c)
|
|
{
|
|
struct i2c_msg *msg = iproc_i2c->msg;
|
|
unsigned int tx_bytes = msg->len - iproc_i2c->tx_bytes;
|
|
unsigned int i;
|
|
u32 val;
|
|
|
|
/* can only fill up to the FIFO size */
|
|
tx_bytes = min_t(unsigned int, tx_bytes, M_TX_RX_FIFO_SIZE);
|
|
for (i = 0; i < tx_bytes; i++) {
|
|
/* start from where we left over */
|
|
unsigned int idx = iproc_i2c->tx_bytes + i;
|
|
|
|
val = msg->buf[idx];
|
|
|
|
/* mark the last byte */
|
|
if (idx == msg->len - 1) {
|
|
val |= BIT(M_TX_WR_STATUS_SHIFT);
|
|
|
|
if (iproc_i2c->irq) {
|
|
u32 tmp;
|
|
|
|
/*
|
|
* Since this is the last byte, we should now
|
|
* disable TX FIFO underrun interrupt
|
|
*/
|
|
tmp = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
|
|
tmp &= ~BIT(IE_M_TX_UNDERRUN_SHIFT);
|
|
iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET,
|
|
tmp);
|
|
}
|
|
}
|
|
|
|
/* load data into TX FIFO */
|
|
iproc_i2c_wr_reg(iproc_i2c, M_TX_OFFSET, val);
|
|
}
|
|
|
|
/* update number of transferred bytes */
|
|
iproc_i2c->tx_bytes += tx_bytes;
|
|
}
|
|
|
|
static void bcm_iproc_i2c_read(struct bcm_iproc_i2c_dev *iproc_i2c)
|
|
{
|
|
struct i2c_msg *msg = iproc_i2c->msg;
|
|
u32 bytes_left, val;
|
|
|
|
bcm_iproc_i2c_read_valid_bytes(iproc_i2c);
|
|
bytes_left = msg->len - iproc_i2c->rx_bytes;
|
|
if (bytes_left == 0) {
|
|
if (iproc_i2c->irq) {
|
|
/* finished reading all data, disable rx thld event */
|
|
val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
|
|
val &= ~BIT(IS_M_RX_THLD_SHIFT);
|
|
iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val);
|
|
}
|
|
} else if (bytes_left < iproc_i2c->thld_bytes) {
|
|
/* set bytes left as threshold */
|
|
val = iproc_i2c_rd_reg(iproc_i2c, M_FIFO_CTRL_OFFSET);
|
|
val &= ~(M_FIFO_RX_THLD_MASK << M_FIFO_RX_THLD_SHIFT);
|
|
val |= (bytes_left << M_FIFO_RX_THLD_SHIFT);
|
|
iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);
|
|
iproc_i2c->thld_bytes = bytes_left;
|
|
}
|
|
/*
|
|
* bytes_left >= iproc_i2c->thld_bytes,
|
|
* hence no need to change the THRESHOLD SET.
|
|
* It will remain as iproc_i2c->thld_bytes itself
|
|
*/
|
|
}
|
|
|
|
static void bcm_iproc_i2c_process_m_event(struct bcm_iproc_i2c_dev *iproc_i2c,
|
|
u32 status)
|
|
{
|
|
/* TX FIFO is empty and we have more data to send */
|
|
if (status & BIT(IS_M_TX_UNDERRUN_SHIFT))
|
|
bcm_iproc_i2c_send(iproc_i2c);
|
|
|
|
/* RX FIFO threshold is reached and data needs to be read out */
|
|
if (status & BIT(IS_M_RX_THLD_SHIFT))
|
|
bcm_iproc_i2c_read(iproc_i2c);
|
|
|
|
/* transfer is done */
|
|
if (status & BIT(IS_M_START_BUSY_SHIFT)) {
|
|
iproc_i2c->xfer_is_done = 1;
|
|
if (iproc_i2c->irq)
|
|
complete(&iproc_i2c->done);
|
|
}
|
|
}
|
|
|
|
static irqreturn_t bcm_iproc_i2c_isr(int irq, void *data)
|
|
{
|
|
struct bcm_iproc_i2c_dev *iproc_i2c = data;
|
|
u32 slave_status;
|
|
u32 status;
|
|
bool ret;
|
|
|
|
status = iproc_i2c_rd_reg(iproc_i2c, IS_OFFSET);
|
|
/* process only slave interrupt which are enabled */
|
|
slave_status = status & iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET) &
|
|
ISR_MASK_SLAVE;
|
|
|
|
if (slave_status) {
|
|
ret = bcm_iproc_i2c_slave_isr(iproc_i2c, slave_status);
|
|
if (ret)
|
|
return IRQ_HANDLED;
|
|
else
|
|
return IRQ_NONE;
|
|
}
|
|
|
|
status &= ISR_MASK;
|
|
if (!status)
|
|
return IRQ_NONE;
|
|
|
|
/* process all master based events */
|
|
bcm_iproc_i2c_process_m_event(iproc_i2c, status);
|
|
iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, status);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static int bcm_iproc_i2c_init(struct bcm_iproc_i2c_dev *iproc_i2c)
|
|
{
|
|
u32 val;
|
|
|
|
/* put controller in reset */
|
|
val = iproc_i2c_rd_reg(iproc_i2c, CFG_OFFSET);
|
|
val |= BIT(CFG_RESET_SHIFT);
|
|
val &= ~(BIT(CFG_EN_SHIFT));
|
|
iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);
|
|
|
|
/* wait 100 usec per spec */
|
|
udelay(100);
|
|
|
|
/* bring controller out of reset */
|
|
val &= ~(BIT(CFG_RESET_SHIFT));
|
|
iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);
|
|
|
|
/* flush TX/RX FIFOs and set RX FIFO threshold to zero */
|
|
val = (BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT));
|
|
iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);
|
|
/* disable all interrupts */
|
|
val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
|
|
val &= ~(IE_M_ALL_INTERRUPT_MASK <<
|
|
IE_M_ALL_INTERRUPT_SHIFT);
|
|
iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val);
|
|
|
|
/* clear all pending interrupts */
|
|
iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, 0xffffffff);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void bcm_iproc_i2c_enable_disable(struct bcm_iproc_i2c_dev *iproc_i2c,
|
|
bool enable)
|
|
{
|
|
u32 val;
|
|
|
|
val = iproc_i2c_rd_reg(iproc_i2c, CFG_OFFSET);
|
|
if (enable)
|
|
val |= BIT(CFG_EN_SHIFT);
|
|
else
|
|
val &= ~BIT(CFG_EN_SHIFT);
|
|
iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);
|
|
}
|
|
|
|
static int bcm_iproc_i2c_check_status(struct bcm_iproc_i2c_dev *iproc_i2c,
|
|
struct i2c_msg *msg)
|
|
{
|
|
u32 val;
|
|
|
|
val = iproc_i2c_rd_reg(iproc_i2c, M_CMD_OFFSET);
|
|
val = (val >> M_CMD_STATUS_SHIFT) & M_CMD_STATUS_MASK;
|
|
|
|
switch (val) {
|
|
case M_CMD_STATUS_SUCCESS:
|
|
return 0;
|
|
|
|
case M_CMD_STATUS_LOST_ARB:
|
|
dev_dbg(iproc_i2c->device, "lost bus arbitration\n");
|
|
return -EAGAIN;
|
|
|
|
case M_CMD_STATUS_NACK_ADDR:
|
|
dev_dbg(iproc_i2c->device, "NAK addr:0x%02x\n", msg->addr);
|
|
return -ENXIO;
|
|
|
|
case M_CMD_STATUS_NACK_DATA:
|
|
dev_dbg(iproc_i2c->device, "NAK data\n");
|
|
return -ENXIO;
|
|
|
|
case M_CMD_STATUS_TIMEOUT:
|
|
dev_dbg(iproc_i2c->device, "bus timeout\n");
|
|
return -ETIMEDOUT;
|
|
|
|
case M_CMD_STATUS_FIFO_UNDERRUN:
|
|
dev_dbg(iproc_i2c->device, "FIFO under-run\n");
|
|
return -ENXIO;
|
|
|
|
case M_CMD_STATUS_RX_FIFO_FULL:
|
|
dev_dbg(iproc_i2c->device, "RX FIFO full\n");
|
|
return -ETIMEDOUT;
|
|
|
|
default:
|
|
dev_dbg(iproc_i2c->device, "unknown error code=%d\n", val);
|
|
|
|
/* re-initialize i2c for recovery */
|
|
bcm_iproc_i2c_enable_disable(iproc_i2c, false);
|
|
bcm_iproc_i2c_init(iproc_i2c);
|
|
bcm_iproc_i2c_enable_disable(iproc_i2c, true);
|
|
|
|
return -EIO;
|
|
}
|
|
}
|
|
|
|
static int bcm_iproc_i2c_xfer_wait(struct bcm_iproc_i2c_dev *iproc_i2c,
|
|
struct i2c_msg *msg,
|
|
u32 cmd)
|
|
{
|
|
unsigned long time_left = msecs_to_jiffies(I2C_TIMEOUT_MSEC);
|
|
u32 val, status;
|
|
int ret;
|
|
|
|
iproc_i2c_wr_reg(iproc_i2c, M_CMD_OFFSET, cmd);
|
|
|
|
if (iproc_i2c->irq) {
|
|
time_left = wait_for_completion_timeout(&iproc_i2c->done,
|
|
time_left);
|
|
/* disable all interrupts */
|
|
iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, 0);
|
|
/* read it back to flush the write */
|
|
iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
|
|
/* make sure the interrupt handler isn't running */
|
|
synchronize_irq(iproc_i2c->irq);
|
|
|
|
} else { /* polling mode */
|
|
unsigned long timeout = jiffies + time_left;
|
|
|
|
do {
|
|
status = iproc_i2c_rd_reg(iproc_i2c,
|
|
IS_OFFSET) & ISR_MASK;
|
|
bcm_iproc_i2c_process_m_event(iproc_i2c, status);
|
|
iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, status);
|
|
|
|
if (time_after(jiffies, timeout)) {
|
|
time_left = 0;
|
|
break;
|
|
}
|
|
|
|
cpu_relax();
|
|
cond_resched();
|
|
} while (!iproc_i2c->xfer_is_done);
|
|
}
|
|
|
|
if (!time_left && !iproc_i2c->xfer_is_done) {
|
|
dev_err(iproc_i2c->device, "transaction timed out\n");
|
|
|
|
/* flush both TX/RX FIFOs */
|
|
val = BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT);
|
|
iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);
|
|
return -ETIMEDOUT;
|
|
}
|
|
|
|
ret = bcm_iproc_i2c_check_status(iproc_i2c, msg);
|
|
if (ret) {
|
|
/* flush both TX/RX FIFOs */
|
|
val = BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT);
|
|
iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);
|
|
return ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* If 'process_call' is true, then this is a multi-msg transfer that requires
|
|
* a repeated start between the messages.
|
|
* More specifically, it must be a write (reg) followed by a read (data).
|
|
* The i2c quirks are set to enforce this rule.
|
|
*/
|
|
static int bcm_iproc_i2c_xfer_internal(struct bcm_iproc_i2c_dev *iproc_i2c,
|
|
struct i2c_msg *msgs, bool process_call)
|
|
{
|
|
int i;
|
|
u8 addr;
|
|
u32 val, tmp, val_intr_en;
|
|
unsigned int tx_bytes;
|
|
struct i2c_msg *msg = &msgs[0];
|
|
|
|
/* check if bus is busy */
|
|
if (!!(iproc_i2c_rd_reg(iproc_i2c,
|
|
M_CMD_OFFSET) & BIT(M_CMD_START_BUSY_SHIFT))) {
|
|
dev_warn(iproc_i2c->device, "bus is busy\n");
|
|
return -EBUSY;
|
|
}
|
|
|
|
iproc_i2c->msg = msg;
|
|
|
|
/* format and load slave address into the TX FIFO */
|
|
addr = i2c_8bit_addr_from_msg(msg);
|
|
iproc_i2c_wr_reg(iproc_i2c, M_TX_OFFSET, addr);
|
|
|
|
/*
|
|
* For a write transaction, load data into the TX FIFO. Only allow
|
|
* loading up to TX FIFO size - 1 bytes of data since the first byte
|
|
* has been used up by the slave address
|
|
*/
|
|
tx_bytes = min_t(unsigned int, msg->len, M_TX_RX_FIFO_SIZE - 1);
|
|
if (!(msg->flags & I2C_M_RD)) {
|
|
for (i = 0; i < tx_bytes; i++) {
|
|
val = msg->buf[i];
|
|
|
|
/* mark the last byte */
|
|
if (!process_call && (i == msg->len - 1))
|
|
val |= BIT(M_TX_WR_STATUS_SHIFT);
|
|
|
|
iproc_i2c_wr_reg(iproc_i2c, M_TX_OFFSET, val);
|
|
}
|
|
iproc_i2c->tx_bytes = tx_bytes;
|
|
}
|
|
|
|
/* Process the read message if this is process call */
|
|
if (process_call) {
|
|
msg++;
|
|
iproc_i2c->msg = msg; /* point to second msg */
|
|
|
|
/*
|
|
* The last byte to be sent out should be a slave
|
|
* address with read operation
|
|
*/
|
|
addr = i2c_8bit_addr_from_msg(msg);
|
|
/* mark it the last byte out */
|
|
val = addr | BIT(M_TX_WR_STATUS_SHIFT);
|
|
iproc_i2c_wr_reg(iproc_i2c, M_TX_OFFSET, val);
|
|
}
|
|
|
|
/* mark as incomplete before starting the transaction */
|
|
if (iproc_i2c->irq)
|
|
reinit_completion(&iproc_i2c->done);
|
|
|
|
iproc_i2c->xfer_is_done = 0;
|
|
|
|
/*
|
|
* Enable the "start busy" interrupt, which will be triggered after the
|
|
* transaction is done, i.e., the internal start_busy bit, transitions
|
|
* from 1 to 0.
|
|
*/
|
|
val_intr_en = BIT(IE_M_START_BUSY_SHIFT);
|
|
|
|
/*
|
|
* If TX data size is larger than the TX FIFO, need to enable TX
|
|
* underrun interrupt, which will be triggerred when the TX FIFO is
|
|
* empty. When that happens we can then pump more data into the FIFO
|
|
*/
|
|
if (!process_call && !(msg->flags & I2C_M_RD) &&
|
|
msg->len > iproc_i2c->tx_bytes)
|
|
val_intr_en |= BIT(IE_M_TX_UNDERRUN_SHIFT);
|
|
|
|
/*
|
|
* Now we can activate the transfer. For a read operation, specify the
|
|
* number of bytes to read
|
|
*/
|
|
val = BIT(M_CMD_START_BUSY_SHIFT);
|
|
|
|
if (msg->len == 0) {
|
|
/* SMBUS QUICK Command (Read/Write) */
|
|
val |= (M_CMD_PROTOCOL_QUICK << M_CMD_PROTOCOL_SHIFT);
|
|
} else if (msg->flags & I2C_M_RD) {
|
|
u32 protocol;
|
|
|
|
iproc_i2c->rx_bytes = 0;
|
|
if (msg->len > M_RX_FIFO_MAX_THLD_VALUE)
|
|
iproc_i2c->thld_bytes = M_RX_FIFO_THLD_VALUE;
|
|
else
|
|
iproc_i2c->thld_bytes = msg->len;
|
|
|
|
/* set threshold value */
|
|
tmp = iproc_i2c_rd_reg(iproc_i2c, M_FIFO_CTRL_OFFSET);
|
|
tmp &= ~(M_FIFO_RX_THLD_MASK << M_FIFO_RX_THLD_SHIFT);
|
|
tmp |= iproc_i2c->thld_bytes << M_FIFO_RX_THLD_SHIFT;
|
|
iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, tmp);
|
|
|
|
/* enable the RX threshold interrupt */
|
|
val_intr_en |= BIT(IE_M_RX_THLD_SHIFT);
|
|
|
|
protocol = process_call ?
|
|
M_CMD_PROTOCOL_PROCESS : M_CMD_PROTOCOL_BLK_RD;
|
|
|
|
val |= (protocol << M_CMD_PROTOCOL_SHIFT) |
|
|
(msg->len << M_CMD_RD_CNT_SHIFT);
|
|
} else {
|
|
val |= (M_CMD_PROTOCOL_BLK_WR << M_CMD_PROTOCOL_SHIFT);
|
|
}
|
|
|
|
if (iproc_i2c->irq)
|
|
iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val_intr_en);
|
|
|
|
return bcm_iproc_i2c_xfer_wait(iproc_i2c, msg, val);
|
|
}
|
|
|
|
static int bcm_iproc_i2c_xfer(struct i2c_adapter *adapter,
|
|
struct i2c_msg msgs[], int num)
|
|
{
|
|
struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(adapter);
|
|
bool process_call = false;
|
|
int ret;
|
|
|
|
if (num == 2) {
|
|
/* Repeated start, use process call */
|
|
process_call = true;
|
|
if (msgs[1].flags & I2C_M_NOSTART) {
|
|
dev_err(iproc_i2c->device, "Invalid repeated start\n");
|
|
return -EOPNOTSUPP;
|
|
}
|
|
}
|
|
|
|
ret = bcm_iproc_i2c_xfer_internal(iproc_i2c, msgs, process_call);
|
|
if (ret) {
|
|
dev_dbg(iproc_i2c->device, "xfer failed\n");
|
|
return ret;
|
|
}
|
|
|
|
return num;
|
|
}
|
|
|
|
static uint32_t bcm_iproc_i2c_functionality(struct i2c_adapter *adap)
|
|
{
|
|
u32 val;
|
|
|
|
val = I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
|
|
|
|
if (adap->algo->reg_slave)
|
|
val |= I2C_FUNC_SLAVE;
|
|
|
|
return val;
|
|
}
|
|
|
|
static struct i2c_algorithm bcm_iproc_algo = {
|
|
.master_xfer = bcm_iproc_i2c_xfer,
|
|
.functionality = bcm_iproc_i2c_functionality,
|
|
.reg_slave = bcm_iproc_i2c_reg_slave,
|
|
.unreg_slave = bcm_iproc_i2c_unreg_slave,
|
|
};
|
|
|
|
static const struct i2c_adapter_quirks bcm_iproc_i2c_quirks = {
|
|
.flags = I2C_AQ_COMB_WRITE_THEN_READ,
|
|
.max_comb_1st_msg_len = M_TX_RX_FIFO_SIZE,
|
|
.max_read_len = M_RX_MAX_READ_LEN,
|
|
};
|
|
|
|
static int bcm_iproc_i2c_cfg_speed(struct bcm_iproc_i2c_dev *iproc_i2c)
|
|
{
|
|
unsigned int bus_speed;
|
|
u32 val;
|
|
int ret = of_property_read_u32(iproc_i2c->device->of_node,
|
|
"clock-frequency", &bus_speed);
|
|
if (ret < 0) {
|
|
dev_info(iproc_i2c->device,
|
|
"unable to interpret clock-frequency DT property\n");
|
|
bus_speed = I2C_MAX_STANDARD_MODE_FREQ;
|
|
}
|
|
|
|
if (bus_speed < I2C_MAX_STANDARD_MODE_FREQ) {
|
|
dev_err(iproc_i2c->device, "%d Hz bus speed not supported\n",
|
|
bus_speed);
|
|
dev_err(iproc_i2c->device,
|
|
"valid speeds are 100khz and 400khz\n");
|
|
return -EINVAL;
|
|
} else if (bus_speed < I2C_MAX_FAST_MODE_FREQ) {
|
|
bus_speed = I2C_MAX_STANDARD_MODE_FREQ;
|
|
} else {
|
|
bus_speed = I2C_MAX_FAST_MODE_FREQ;
|
|
}
|
|
|
|
iproc_i2c->bus_speed = bus_speed;
|
|
val = iproc_i2c_rd_reg(iproc_i2c, TIM_CFG_OFFSET);
|
|
val &= ~BIT(TIM_CFG_MODE_400_SHIFT);
|
|
val |= (bus_speed == I2C_MAX_FAST_MODE_FREQ) << TIM_CFG_MODE_400_SHIFT;
|
|
iproc_i2c_wr_reg(iproc_i2c, TIM_CFG_OFFSET, val);
|
|
|
|
dev_info(iproc_i2c->device, "bus set to %u Hz\n", bus_speed);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int bcm_iproc_i2c_probe(struct platform_device *pdev)
|
|
{
|
|
int irq, ret = 0;
|
|
struct bcm_iproc_i2c_dev *iproc_i2c;
|
|
struct i2c_adapter *adap;
|
|
struct resource *res;
|
|
|
|
iproc_i2c = devm_kzalloc(&pdev->dev, sizeof(*iproc_i2c),
|
|
GFP_KERNEL);
|
|
if (!iproc_i2c)
|
|
return -ENOMEM;
|
|
|
|
platform_set_drvdata(pdev, iproc_i2c);
|
|
iproc_i2c->device = &pdev->dev;
|
|
iproc_i2c->type =
|
|
(enum bcm_iproc_i2c_type)of_device_get_match_data(&pdev->dev);
|
|
init_completion(&iproc_i2c->done);
|
|
|
|
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
iproc_i2c->base = devm_ioremap_resource(iproc_i2c->device, res);
|
|
if (IS_ERR(iproc_i2c->base))
|
|
return PTR_ERR(iproc_i2c->base);
|
|
|
|
if (iproc_i2c->type == IPROC_I2C_NIC) {
|
|
res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
|
|
iproc_i2c->idm_base = devm_ioremap_resource(iproc_i2c->device,
|
|
res);
|
|
if (IS_ERR(iproc_i2c->idm_base))
|
|
return PTR_ERR(iproc_i2c->idm_base);
|
|
|
|
ret = of_property_read_u32(iproc_i2c->device->of_node,
|
|
"brcm,ape-hsls-addr-mask",
|
|
&iproc_i2c->ape_addr_mask);
|
|
if (ret < 0) {
|
|
dev_err(iproc_i2c->device,
|
|
"'brcm,ape-hsls-addr-mask' missing\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
spin_lock_init(&iproc_i2c->idm_lock);
|
|
|
|
/* no slave support */
|
|
bcm_iproc_algo.reg_slave = NULL;
|
|
bcm_iproc_algo.unreg_slave = NULL;
|
|
}
|
|
|
|
ret = bcm_iproc_i2c_init(iproc_i2c);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = bcm_iproc_i2c_cfg_speed(iproc_i2c);
|
|
if (ret)
|
|
return ret;
|
|
|
|
irq = platform_get_irq(pdev, 0);
|
|
if (irq > 0) {
|
|
ret = devm_request_irq(iproc_i2c->device, irq,
|
|
bcm_iproc_i2c_isr, 0, pdev->name,
|
|
iproc_i2c);
|
|
if (ret < 0) {
|
|
dev_err(iproc_i2c->device,
|
|
"unable to request irq %i\n", irq);
|
|
return ret;
|
|
}
|
|
|
|
iproc_i2c->irq = irq;
|
|
} else {
|
|
dev_warn(iproc_i2c->device,
|
|
"no irq resource, falling back to poll mode\n");
|
|
}
|
|
|
|
bcm_iproc_i2c_enable_disable(iproc_i2c, true);
|
|
|
|
adap = &iproc_i2c->adapter;
|
|
i2c_set_adapdata(adap, iproc_i2c);
|
|
snprintf(adap->name, sizeof(adap->name),
|
|
"Broadcom iProc (%s)",
|
|
of_node_full_name(iproc_i2c->device->of_node));
|
|
adap->algo = &bcm_iproc_algo;
|
|
adap->quirks = &bcm_iproc_i2c_quirks;
|
|
adap->dev.parent = &pdev->dev;
|
|
adap->dev.of_node = pdev->dev.of_node;
|
|
|
|
return i2c_add_adapter(adap);
|
|
}
|
|
|
|
static int bcm_iproc_i2c_remove(struct platform_device *pdev)
|
|
{
|
|
struct bcm_iproc_i2c_dev *iproc_i2c = platform_get_drvdata(pdev);
|
|
|
|
if (iproc_i2c->irq) {
|
|
/*
|
|
* Make sure there's no pending interrupt when we remove the
|
|
* adapter
|
|
*/
|
|
iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, 0);
|
|
iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
|
|
synchronize_irq(iproc_i2c->irq);
|
|
}
|
|
|
|
i2c_del_adapter(&iproc_i2c->adapter);
|
|
bcm_iproc_i2c_enable_disable(iproc_i2c, false);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_PM_SLEEP
|
|
|
|
static int bcm_iproc_i2c_suspend(struct device *dev)
|
|
{
|
|
struct bcm_iproc_i2c_dev *iproc_i2c = dev_get_drvdata(dev);
|
|
|
|
if (iproc_i2c->irq) {
|
|
/*
|
|
* Make sure there's no pending interrupt when we go into
|
|
* suspend
|
|
*/
|
|
iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, 0);
|
|
iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
|
|
synchronize_irq(iproc_i2c->irq);
|
|
}
|
|
|
|
/* now disable the controller */
|
|
bcm_iproc_i2c_enable_disable(iproc_i2c, false);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int bcm_iproc_i2c_resume(struct device *dev)
|
|
{
|
|
struct bcm_iproc_i2c_dev *iproc_i2c = dev_get_drvdata(dev);
|
|
int ret;
|
|
u32 val;
|
|
|
|
/*
|
|
* Power domain could have been shut off completely in system deep
|
|
* sleep, so re-initialize the block here
|
|
*/
|
|
ret = bcm_iproc_i2c_init(iproc_i2c);
|
|
if (ret)
|
|
return ret;
|
|
|
|
/* configure to the desired bus speed */
|
|
val = iproc_i2c_rd_reg(iproc_i2c, TIM_CFG_OFFSET);
|
|
val &= ~BIT(TIM_CFG_MODE_400_SHIFT);
|
|
val |= (iproc_i2c->bus_speed == I2C_MAX_FAST_MODE_FREQ) << TIM_CFG_MODE_400_SHIFT;
|
|
iproc_i2c_wr_reg(iproc_i2c, TIM_CFG_OFFSET, val);
|
|
|
|
bcm_iproc_i2c_enable_disable(iproc_i2c, true);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct dev_pm_ops bcm_iproc_i2c_pm_ops = {
|
|
.suspend_late = &bcm_iproc_i2c_suspend,
|
|
.resume_early = &bcm_iproc_i2c_resume
|
|
};
|
|
|
|
#define BCM_IPROC_I2C_PM_OPS (&bcm_iproc_i2c_pm_ops)
|
|
#else
|
|
#define BCM_IPROC_I2C_PM_OPS NULL
|
|
#endif /* CONFIG_PM_SLEEP */
|
|
|
|
|
|
static int bcm_iproc_i2c_reg_slave(struct i2c_client *slave)
|
|
{
|
|
struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(slave->adapter);
|
|
|
|
if (iproc_i2c->slave)
|
|
return -EBUSY;
|
|
|
|
if (slave->flags & I2C_CLIENT_TEN)
|
|
return -EAFNOSUPPORT;
|
|
|
|
iproc_i2c->slave = slave;
|
|
|
|
tasklet_init(&iproc_i2c->slave_rx_tasklet, slave_rx_tasklet_fn,
|
|
(unsigned long)iproc_i2c);
|
|
|
|
bcm_iproc_i2c_slave_init(iproc_i2c, false);
|
|
return 0;
|
|
}
|
|
|
|
static int bcm_iproc_i2c_unreg_slave(struct i2c_client *slave)
|
|
{
|
|
u32 tmp;
|
|
struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(slave->adapter);
|
|
|
|
if (!iproc_i2c->slave)
|
|
return -EINVAL;
|
|
|
|
disable_irq(iproc_i2c->irq);
|
|
|
|
/* disable all slave interrupts */
|
|
tmp = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
|
|
tmp &= ~(IE_S_ALL_INTERRUPT_MASK <<
|
|
IE_S_ALL_INTERRUPT_SHIFT);
|
|
iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, tmp);
|
|
|
|
tasklet_kill(&iproc_i2c->slave_rx_tasklet);
|
|
|
|
/* Erase the slave address programmed */
|
|
tmp = iproc_i2c_rd_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET);
|
|
tmp &= ~BIT(S_CFG_EN_NIC_SMB_ADDR3_SHIFT);
|
|
iproc_i2c_wr_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET, tmp);
|
|
|
|
/* flush TX/RX FIFOs */
|
|
tmp = (BIT(S_FIFO_RX_FLUSH_SHIFT) | BIT(S_FIFO_TX_FLUSH_SHIFT));
|
|
iproc_i2c_wr_reg(iproc_i2c, S_FIFO_CTRL_OFFSET, tmp);
|
|
|
|
/* clear all pending slave interrupts */
|
|
iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, ISR_MASK_SLAVE);
|
|
|
|
iproc_i2c->slave = NULL;
|
|
|
|
enable_irq(iproc_i2c->irq);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct of_device_id bcm_iproc_i2c_of_match[] = {
|
|
{
|
|
.compatible = "brcm,iproc-i2c",
|
|
.data = (int *)IPROC_I2C,
|
|
}, {
|
|
.compatible = "brcm,iproc-nic-i2c",
|
|
.data = (int *)IPROC_I2C_NIC,
|
|
},
|
|
{ /* sentinel */ }
|
|
};
|
|
MODULE_DEVICE_TABLE(of, bcm_iproc_i2c_of_match);
|
|
|
|
static struct platform_driver bcm_iproc_i2c_driver = {
|
|
.driver = {
|
|
.name = "bcm-iproc-i2c",
|
|
.of_match_table = bcm_iproc_i2c_of_match,
|
|
.pm = BCM_IPROC_I2C_PM_OPS,
|
|
},
|
|
.probe = bcm_iproc_i2c_probe,
|
|
.remove = bcm_iproc_i2c_remove,
|
|
};
|
|
module_platform_driver(bcm_iproc_i2c_driver);
|
|
|
|
MODULE_AUTHOR("Ray Jui <rjui@broadcom.com>");
|
|
MODULE_DESCRIPTION("Broadcom iProc I2C Driver");
|
|
MODULE_LICENSE("GPL v2");
|