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https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
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ca6961d8a8
The mcp2221_raw_event retrieves the value and direction of gpio on the same command, by setting the value on mcp->status and the direction on mcp->gpio_dir; and the offset at which they are read is based on mcp->gp_idx, set by the gpiochip callbacks. However, the individual gpiochip calls set the index to look for directly on the field they want to track. This create a "double offset" in the final read in the response report. Align the behaviour of mcp2221_raw_event and mcp_gpio_get/mcp_gpio_get_direction by putting gp_idx on those calls to the base offset of the gpio status struct. Signed-off-by: Louis Morhet <lmorhet@kalrayinc.com> Link: https://lore.kernel.org/r/dd0b23800a79d2a464e1e9ed429b018b69fd5df2.1680602387.git.lmorhet@kalrayinc.com Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
1216 lines
27 KiB
C
1216 lines
27 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* MCP2221A - Microchip USB to I2C Host Protocol Bridge
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*
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* Copyright (c) 2020, Rishi Gupta <gupt21@gmail.com>
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*
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* Datasheet: https://ww1.microchip.com/downloads/en/DeviceDoc/20005565B.pdf
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*/
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#include <linux/module.h>
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#include <linux/err.h>
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#include <linux/mutex.h>
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#include <linux/bitfield.h>
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#include <linux/completion.h>
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#include <linux/delay.h>
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#include <linux/hid.h>
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#include <linux/hidraw.h>
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#include <linux/i2c.h>
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#include <linux/gpio/driver.h>
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#include <linux/iio/iio.h>
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#include "hid-ids.h"
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/* Commands codes in a raw output report */
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enum {
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MCP2221_I2C_WR_DATA = 0x90,
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MCP2221_I2C_WR_NO_STOP = 0x94,
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MCP2221_I2C_RD_DATA = 0x91,
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MCP2221_I2C_RD_RPT_START = 0x93,
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MCP2221_I2C_GET_DATA = 0x40,
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MCP2221_I2C_PARAM_OR_STATUS = 0x10,
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MCP2221_I2C_SET_SPEED = 0x20,
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MCP2221_I2C_CANCEL = 0x10,
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MCP2221_GPIO_SET = 0x50,
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MCP2221_GPIO_GET = 0x51,
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MCP2221_SET_SRAM_SETTINGS = 0x60,
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MCP2221_GET_SRAM_SETTINGS = 0x61,
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MCP2221_READ_FLASH_DATA = 0xb0,
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};
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/* Response codes in a raw input report */
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enum {
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MCP2221_SUCCESS = 0x00,
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MCP2221_I2C_ENG_BUSY = 0x01,
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MCP2221_I2C_START_TOUT = 0x12,
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MCP2221_I2C_STOP_TOUT = 0x62,
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MCP2221_I2C_WRADDRL_TOUT = 0x23,
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MCP2221_I2C_WRDATA_TOUT = 0x44,
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MCP2221_I2C_WRADDRL_NACK = 0x25,
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MCP2221_I2C_MASK_ADDR_NACK = 0x40,
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MCP2221_I2C_WRADDRL_SEND = 0x21,
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MCP2221_I2C_ADDR_NACK = 0x25,
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MCP2221_I2C_READ_COMPL = 0x55,
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MCP2221_ALT_F_NOT_GPIOV = 0xEE,
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MCP2221_ALT_F_NOT_GPIOD = 0xEF,
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};
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/* MCP GPIO direction encoding */
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enum {
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MCP2221_DIR_OUT = 0x00,
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MCP2221_DIR_IN = 0x01,
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};
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#define MCP_NGPIO 4
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/* MCP GPIO set command layout */
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struct mcp_set_gpio {
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u8 cmd;
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u8 dummy;
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struct {
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u8 change_value;
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u8 value;
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u8 change_direction;
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u8 direction;
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} gpio[MCP_NGPIO];
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} __packed;
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/* MCP GPIO get command layout */
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struct mcp_get_gpio {
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u8 cmd;
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u8 dummy;
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struct {
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u8 value;
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u8 direction;
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} gpio[MCP_NGPIO];
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} __packed;
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/*
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* There is no way to distinguish responses. Therefore next command
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* is sent only after response to previous has been received. Mutex
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* lock is used for this purpose mainly.
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*/
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struct mcp2221 {
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struct hid_device *hdev;
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struct i2c_adapter adapter;
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struct mutex lock;
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struct completion wait_in_report;
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struct delayed_work init_work;
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u8 *rxbuf;
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u8 txbuf[64];
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int rxbuf_idx;
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int status;
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u8 cur_i2c_clk_div;
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struct gpio_chip *gc;
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u8 gp_idx;
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u8 gpio_dir;
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u8 mode[4];
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#if IS_REACHABLE(CONFIG_IIO)
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struct iio_chan_spec iio_channels[3];
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u16 adc_values[3];
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u8 adc_scale;
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u8 dac_value;
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u16 dac_scale;
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#endif
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};
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struct mcp2221_iio {
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struct mcp2221 *mcp;
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};
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/*
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* Default i2c bus clock frequency 400 kHz. Modify this if you
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* want to set some other frequency (min 50 kHz - max 400 kHz).
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*/
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static uint i2c_clk_freq = 400;
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/* Synchronously send output report to the device */
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static int mcp_send_report(struct mcp2221 *mcp,
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u8 *out_report, size_t len)
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{
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u8 *buf;
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int ret;
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buf = kmemdup(out_report, len, GFP_KERNEL);
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if (!buf)
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return -ENOMEM;
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/* mcp2221 uses interrupt endpoint for out reports */
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ret = hid_hw_output_report(mcp->hdev, buf, len);
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kfree(buf);
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if (ret < 0)
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return ret;
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return 0;
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}
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/*
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* Send o/p report to the device and wait for i/p report to be
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* received from the device. If the device does not respond,
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* we timeout.
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*/
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static int mcp_send_data_req_status(struct mcp2221 *mcp,
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u8 *out_report, int len)
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{
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int ret;
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unsigned long t;
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reinit_completion(&mcp->wait_in_report);
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ret = mcp_send_report(mcp, out_report, len);
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if (ret)
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return ret;
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t = wait_for_completion_timeout(&mcp->wait_in_report,
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msecs_to_jiffies(4000));
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if (!t)
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return -ETIMEDOUT;
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return mcp->status;
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}
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/* Check pass/fail for actual communication with i2c slave */
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static int mcp_chk_last_cmd_status(struct mcp2221 *mcp)
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{
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memset(mcp->txbuf, 0, 8);
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mcp->txbuf[0] = MCP2221_I2C_PARAM_OR_STATUS;
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return mcp_send_data_req_status(mcp, mcp->txbuf, 8);
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}
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/* Cancels last command releasing i2c bus just in case occupied */
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static int mcp_cancel_last_cmd(struct mcp2221 *mcp)
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{
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memset(mcp->txbuf, 0, 8);
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mcp->txbuf[0] = MCP2221_I2C_PARAM_OR_STATUS;
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mcp->txbuf[2] = MCP2221_I2C_CANCEL;
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return mcp_send_data_req_status(mcp, mcp->txbuf, 8);
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}
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static int mcp_set_i2c_speed(struct mcp2221 *mcp)
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{
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int ret;
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memset(mcp->txbuf, 0, 8);
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mcp->txbuf[0] = MCP2221_I2C_PARAM_OR_STATUS;
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mcp->txbuf[3] = MCP2221_I2C_SET_SPEED;
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mcp->txbuf[4] = mcp->cur_i2c_clk_div;
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ret = mcp_send_data_req_status(mcp, mcp->txbuf, 8);
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if (ret) {
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/* Small delay is needed here */
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usleep_range(980, 1000);
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mcp_cancel_last_cmd(mcp);
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}
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return 0;
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}
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/*
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* An output report can contain minimum 1 and maximum 60 user data
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* bytes. If the number of data bytes is more then 60, we send it
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* in chunks of 60 bytes. Last chunk may contain exactly 60 or less
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* bytes. Total number of bytes is informed in very first report to
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* mcp2221, from that point onwards it first collect all the data
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* from host and then send to i2c slave device.
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*/
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static int mcp_i2c_write(struct mcp2221 *mcp,
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struct i2c_msg *msg, int type, u8 last_status)
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{
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int ret, len, idx, sent;
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idx = 0;
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sent = 0;
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if (msg->len < 60)
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len = msg->len;
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else
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len = 60;
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do {
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mcp->txbuf[0] = type;
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mcp->txbuf[1] = msg->len & 0xff;
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mcp->txbuf[2] = msg->len >> 8;
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mcp->txbuf[3] = (u8)(msg->addr << 1);
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memcpy(&mcp->txbuf[4], &msg->buf[idx], len);
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ret = mcp_send_data_req_status(mcp, mcp->txbuf, len + 4);
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if (ret)
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return ret;
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usleep_range(980, 1000);
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if (last_status) {
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ret = mcp_chk_last_cmd_status(mcp);
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if (ret)
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return ret;
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}
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sent = sent + len;
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if (sent >= msg->len)
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break;
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idx = idx + len;
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if ((msg->len - sent) < 60)
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len = msg->len - sent;
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else
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len = 60;
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/*
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* Testing shows delay is needed between successive writes
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* otherwise next write fails on first-try from i2c core.
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* This value is obtained through automated stress testing.
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*/
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usleep_range(980, 1000);
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} while (len > 0);
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return ret;
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}
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/*
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* Device reads all data (0 - 65535 bytes) from i2c slave device and
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* stores it in device itself. This data is read back from device to
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* host in multiples of 60 bytes using input reports.
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*/
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static int mcp_i2c_smbus_read(struct mcp2221 *mcp,
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struct i2c_msg *msg, int type, u16 smbus_addr,
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u8 smbus_len, u8 *smbus_buf)
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{
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int ret;
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u16 total_len;
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mcp->txbuf[0] = type;
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if (msg) {
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mcp->txbuf[1] = msg->len & 0xff;
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mcp->txbuf[2] = msg->len >> 8;
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mcp->txbuf[3] = (u8)(msg->addr << 1);
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total_len = msg->len;
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mcp->rxbuf = msg->buf;
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} else {
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mcp->txbuf[1] = smbus_len;
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mcp->txbuf[2] = 0;
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mcp->txbuf[3] = (u8)(smbus_addr << 1);
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total_len = smbus_len;
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mcp->rxbuf = smbus_buf;
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}
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ret = mcp_send_data_req_status(mcp, mcp->txbuf, 4);
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if (ret)
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return ret;
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mcp->rxbuf_idx = 0;
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do {
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memset(mcp->txbuf, 0, 4);
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mcp->txbuf[0] = MCP2221_I2C_GET_DATA;
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ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1);
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if (ret)
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return ret;
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ret = mcp_chk_last_cmd_status(mcp);
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if (ret)
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return ret;
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usleep_range(980, 1000);
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} while (mcp->rxbuf_idx < total_len);
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return ret;
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}
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static int mcp_i2c_xfer(struct i2c_adapter *adapter,
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struct i2c_msg msgs[], int num)
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{
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int ret;
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struct mcp2221 *mcp = i2c_get_adapdata(adapter);
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hid_hw_power(mcp->hdev, PM_HINT_FULLON);
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mutex_lock(&mcp->lock);
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/* Setting speed before every transaction is required for mcp2221 */
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ret = mcp_set_i2c_speed(mcp);
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if (ret)
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goto exit;
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if (num == 1) {
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if (msgs->flags & I2C_M_RD) {
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ret = mcp_i2c_smbus_read(mcp, msgs, MCP2221_I2C_RD_DATA,
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0, 0, NULL);
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} else {
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ret = mcp_i2c_write(mcp, msgs, MCP2221_I2C_WR_DATA, 1);
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}
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if (ret)
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goto exit;
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ret = num;
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} else if (num == 2) {
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/* Ex transaction; send reg address and read its contents */
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if (msgs[0].addr == msgs[1].addr &&
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!(msgs[0].flags & I2C_M_RD) &&
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(msgs[1].flags & I2C_M_RD)) {
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ret = mcp_i2c_write(mcp, &msgs[0],
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MCP2221_I2C_WR_NO_STOP, 0);
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if (ret)
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goto exit;
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ret = mcp_i2c_smbus_read(mcp, &msgs[1],
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MCP2221_I2C_RD_RPT_START,
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0, 0, NULL);
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if (ret)
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goto exit;
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ret = num;
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} else {
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dev_err(&adapter->dev,
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"unsupported multi-msg i2c transaction\n");
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ret = -EOPNOTSUPP;
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}
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} else {
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dev_err(&adapter->dev,
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"unsupported multi-msg i2c transaction\n");
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ret = -EOPNOTSUPP;
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}
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exit:
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hid_hw_power(mcp->hdev, PM_HINT_NORMAL);
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mutex_unlock(&mcp->lock);
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return ret;
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}
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static int mcp_smbus_write(struct mcp2221 *mcp, u16 addr,
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u8 command, u8 *buf, u8 len, int type,
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u8 last_status)
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{
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int data_len, ret;
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mcp->txbuf[0] = type;
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mcp->txbuf[1] = len + 1; /* 1 is due to command byte itself */
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mcp->txbuf[2] = 0;
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mcp->txbuf[3] = (u8)(addr << 1);
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mcp->txbuf[4] = command;
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switch (len) {
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case 0:
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data_len = 5;
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break;
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case 1:
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mcp->txbuf[5] = buf[0];
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data_len = 6;
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break;
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case 2:
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mcp->txbuf[5] = buf[0];
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mcp->txbuf[6] = buf[1];
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data_len = 7;
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break;
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default:
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if (len > I2C_SMBUS_BLOCK_MAX)
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return -EINVAL;
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memcpy(&mcp->txbuf[5], buf, len);
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data_len = len + 5;
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}
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ret = mcp_send_data_req_status(mcp, mcp->txbuf, data_len);
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if (ret)
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return ret;
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if (last_status) {
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usleep_range(980, 1000);
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ret = mcp_chk_last_cmd_status(mcp);
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if (ret)
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return ret;
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}
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return ret;
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}
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|
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static int mcp_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
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unsigned short flags, char read_write,
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u8 command, int size,
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union i2c_smbus_data *data)
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{
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int ret;
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struct mcp2221 *mcp = i2c_get_adapdata(adapter);
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hid_hw_power(mcp->hdev, PM_HINT_FULLON);
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mutex_lock(&mcp->lock);
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ret = mcp_set_i2c_speed(mcp);
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if (ret)
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goto exit;
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switch (size) {
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case I2C_SMBUS_QUICK:
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if (read_write == I2C_SMBUS_READ)
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ret = mcp_i2c_smbus_read(mcp, NULL, MCP2221_I2C_RD_DATA,
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addr, 0, &data->byte);
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else
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ret = mcp_smbus_write(mcp, addr, command, NULL,
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0, MCP2221_I2C_WR_DATA, 1);
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break;
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case I2C_SMBUS_BYTE:
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if (read_write == I2C_SMBUS_READ)
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ret = mcp_i2c_smbus_read(mcp, NULL, MCP2221_I2C_RD_DATA,
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addr, 1, &data->byte);
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else
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ret = mcp_smbus_write(mcp, addr, command, NULL,
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0, MCP2221_I2C_WR_DATA, 1);
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break;
|
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case I2C_SMBUS_BYTE_DATA:
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if (read_write == I2C_SMBUS_READ) {
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ret = mcp_smbus_write(mcp, addr, command, NULL,
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0, MCP2221_I2C_WR_NO_STOP, 0);
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if (ret)
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goto exit;
|
|
|
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ret = mcp_i2c_smbus_read(mcp, NULL,
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MCP2221_I2C_RD_RPT_START,
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addr, 1, &data->byte);
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} else {
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ret = mcp_smbus_write(mcp, addr, command, &data->byte,
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1, MCP2221_I2C_WR_DATA, 1);
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}
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break;
|
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case I2C_SMBUS_WORD_DATA:
|
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if (read_write == I2C_SMBUS_READ) {
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ret = mcp_smbus_write(mcp, addr, command, NULL,
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0, MCP2221_I2C_WR_NO_STOP, 0);
|
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if (ret)
|
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goto exit;
|
|
|
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ret = mcp_i2c_smbus_read(mcp, NULL,
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MCP2221_I2C_RD_RPT_START,
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addr, 2, (u8 *)&data->word);
|
|
} else {
|
|
ret = mcp_smbus_write(mcp, addr, command,
|
|
(u8 *)&data->word, 2,
|
|
MCP2221_I2C_WR_DATA, 1);
|
|
}
|
|
break;
|
|
case I2C_SMBUS_BLOCK_DATA:
|
|
if (read_write == I2C_SMBUS_READ) {
|
|
ret = mcp_smbus_write(mcp, addr, command, NULL,
|
|
0, MCP2221_I2C_WR_NO_STOP, 1);
|
|
if (ret)
|
|
goto exit;
|
|
|
|
mcp->rxbuf_idx = 0;
|
|
mcp->rxbuf = data->block;
|
|
mcp->txbuf[0] = MCP2221_I2C_GET_DATA;
|
|
ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1);
|
|
if (ret)
|
|
goto exit;
|
|
} else {
|
|
if (!data->block[0]) {
|
|
ret = -EINVAL;
|
|
goto exit;
|
|
}
|
|
ret = mcp_smbus_write(mcp, addr, command, data->block,
|
|
data->block[0] + 1,
|
|
MCP2221_I2C_WR_DATA, 1);
|
|
}
|
|
break;
|
|
case I2C_SMBUS_I2C_BLOCK_DATA:
|
|
if (read_write == I2C_SMBUS_READ) {
|
|
ret = mcp_smbus_write(mcp, addr, command, NULL,
|
|
0, MCP2221_I2C_WR_NO_STOP, 1);
|
|
if (ret)
|
|
goto exit;
|
|
|
|
mcp->rxbuf_idx = 0;
|
|
mcp->rxbuf = data->block;
|
|
mcp->txbuf[0] = MCP2221_I2C_GET_DATA;
|
|
ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1);
|
|
if (ret)
|
|
goto exit;
|
|
} else {
|
|
if (!data->block[0]) {
|
|
ret = -EINVAL;
|
|
goto exit;
|
|
}
|
|
ret = mcp_smbus_write(mcp, addr, command,
|
|
&data->block[1], data->block[0],
|
|
MCP2221_I2C_WR_DATA, 1);
|
|
}
|
|
break;
|
|
case I2C_SMBUS_PROC_CALL:
|
|
ret = mcp_smbus_write(mcp, addr, command,
|
|
(u8 *)&data->word,
|
|
2, MCP2221_I2C_WR_NO_STOP, 0);
|
|
if (ret)
|
|
goto exit;
|
|
|
|
ret = mcp_i2c_smbus_read(mcp, NULL,
|
|
MCP2221_I2C_RD_RPT_START,
|
|
addr, 2, (u8 *)&data->word);
|
|
break;
|
|
case I2C_SMBUS_BLOCK_PROC_CALL:
|
|
ret = mcp_smbus_write(mcp, addr, command, data->block,
|
|
data->block[0] + 1,
|
|
MCP2221_I2C_WR_NO_STOP, 0);
|
|
if (ret)
|
|
goto exit;
|
|
|
|
ret = mcp_i2c_smbus_read(mcp, NULL,
|
|
MCP2221_I2C_RD_RPT_START,
|
|
addr, I2C_SMBUS_BLOCK_MAX,
|
|
data->block);
|
|
break;
|
|
default:
|
|
dev_err(&mcp->adapter.dev,
|
|
"unsupported smbus transaction size:%d\n", size);
|
|
ret = -EOPNOTSUPP;
|
|
}
|
|
|
|
exit:
|
|
hid_hw_power(mcp->hdev, PM_HINT_NORMAL);
|
|
mutex_unlock(&mcp->lock);
|
|
return ret;
|
|
}
|
|
|
|
static u32 mcp_i2c_func(struct i2c_adapter *adapter)
|
|
{
|
|
return I2C_FUNC_I2C |
|
|
I2C_FUNC_SMBUS_READ_BLOCK_DATA |
|
|
I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
|
|
(I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_PEC);
|
|
}
|
|
|
|
static const struct i2c_algorithm mcp_i2c_algo = {
|
|
.master_xfer = mcp_i2c_xfer,
|
|
.smbus_xfer = mcp_smbus_xfer,
|
|
.functionality = mcp_i2c_func,
|
|
};
|
|
|
|
#if IS_REACHABLE(CONFIG_GPIOLIB)
|
|
static int mcp_gpio_get(struct gpio_chip *gc,
|
|
unsigned int offset)
|
|
{
|
|
int ret;
|
|
struct mcp2221 *mcp = gpiochip_get_data(gc);
|
|
|
|
mcp->txbuf[0] = MCP2221_GPIO_GET;
|
|
|
|
mcp->gp_idx = offsetof(struct mcp_get_gpio, gpio[offset]);
|
|
|
|
mutex_lock(&mcp->lock);
|
|
ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1);
|
|
mutex_unlock(&mcp->lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void mcp_gpio_set(struct gpio_chip *gc,
|
|
unsigned int offset, int value)
|
|
{
|
|
struct mcp2221 *mcp = gpiochip_get_data(gc);
|
|
|
|
memset(mcp->txbuf, 0, 18);
|
|
mcp->txbuf[0] = MCP2221_GPIO_SET;
|
|
|
|
mcp->gp_idx = offsetof(struct mcp_set_gpio, gpio[offset].value);
|
|
|
|
mcp->txbuf[mcp->gp_idx - 1] = 1;
|
|
mcp->txbuf[mcp->gp_idx] = !!value;
|
|
|
|
mutex_lock(&mcp->lock);
|
|
mcp_send_data_req_status(mcp, mcp->txbuf, 18);
|
|
mutex_unlock(&mcp->lock);
|
|
}
|
|
|
|
static int mcp_gpio_dir_set(struct mcp2221 *mcp,
|
|
unsigned int offset, u8 val)
|
|
{
|
|
memset(mcp->txbuf, 0, 18);
|
|
mcp->txbuf[0] = MCP2221_GPIO_SET;
|
|
|
|
mcp->gp_idx = offsetof(struct mcp_set_gpio, gpio[offset].direction);
|
|
|
|
mcp->txbuf[mcp->gp_idx - 1] = 1;
|
|
mcp->txbuf[mcp->gp_idx] = val;
|
|
|
|
return mcp_send_data_req_status(mcp, mcp->txbuf, 18);
|
|
}
|
|
|
|
static int mcp_gpio_direction_input(struct gpio_chip *gc,
|
|
unsigned int offset)
|
|
{
|
|
int ret;
|
|
struct mcp2221 *mcp = gpiochip_get_data(gc);
|
|
|
|
mutex_lock(&mcp->lock);
|
|
ret = mcp_gpio_dir_set(mcp, offset, MCP2221_DIR_IN);
|
|
mutex_unlock(&mcp->lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int mcp_gpio_direction_output(struct gpio_chip *gc,
|
|
unsigned int offset, int value)
|
|
{
|
|
int ret;
|
|
struct mcp2221 *mcp = gpiochip_get_data(gc);
|
|
|
|
mutex_lock(&mcp->lock);
|
|
ret = mcp_gpio_dir_set(mcp, offset, MCP2221_DIR_OUT);
|
|
mutex_unlock(&mcp->lock);
|
|
|
|
/* Can't configure as output, bailout early */
|
|
if (ret)
|
|
return ret;
|
|
|
|
mcp_gpio_set(gc, offset, value);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int mcp_gpio_get_direction(struct gpio_chip *gc,
|
|
unsigned int offset)
|
|
{
|
|
int ret;
|
|
struct mcp2221 *mcp = gpiochip_get_data(gc);
|
|
|
|
mcp->txbuf[0] = MCP2221_GPIO_GET;
|
|
|
|
mcp->gp_idx = offsetof(struct mcp_get_gpio, gpio[offset]);
|
|
|
|
mutex_lock(&mcp->lock);
|
|
ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1);
|
|
mutex_unlock(&mcp->lock);
|
|
|
|
if (ret)
|
|
return ret;
|
|
|
|
if (mcp->gpio_dir == MCP2221_DIR_IN)
|
|
return GPIO_LINE_DIRECTION_IN;
|
|
|
|
return GPIO_LINE_DIRECTION_OUT;
|
|
}
|
|
#endif
|
|
|
|
/* Gives current state of i2c engine inside mcp2221 */
|
|
static int mcp_get_i2c_eng_state(struct mcp2221 *mcp,
|
|
u8 *data, u8 idx)
|
|
{
|
|
int ret;
|
|
|
|
switch (data[idx]) {
|
|
case MCP2221_I2C_WRADDRL_NACK:
|
|
case MCP2221_I2C_WRADDRL_SEND:
|
|
ret = -ENXIO;
|
|
break;
|
|
case MCP2221_I2C_START_TOUT:
|
|
case MCP2221_I2C_STOP_TOUT:
|
|
case MCP2221_I2C_WRADDRL_TOUT:
|
|
case MCP2221_I2C_WRDATA_TOUT:
|
|
ret = -ETIMEDOUT;
|
|
break;
|
|
case MCP2221_I2C_ENG_BUSY:
|
|
ret = -EAGAIN;
|
|
break;
|
|
case MCP2221_SUCCESS:
|
|
ret = 0x00;
|
|
break;
|
|
default:
|
|
ret = -EIO;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* MCP2221 uses interrupt endpoint for input reports. This function
|
|
* is called by HID layer when it receives i/p report from mcp2221,
|
|
* which is actually a response to the previously sent command.
|
|
*
|
|
* MCP2221A firmware specific return codes are parsed and 0 or
|
|
* appropriate negative error code is returned. Delayed response
|
|
* results in timeout error and stray reponses results in -EIO.
|
|
*/
|
|
static int mcp2221_raw_event(struct hid_device *hdev,
|
|
struct hid_report *report, u8 *data, int size)
|
|
{
|
|
u8 *buf;
|
|
struct mcp2221 *mcp = hid_get_drvdata(hdev);
|
|
|
|
switch (data[0]) {
|
|
|
|
case MCP2221_I2C_WR_DATA:
|
|
case MCP2221_I2C_WR_NO_STOP:
|
|
case MCP2221_I2C_RD_DATA:
|
|
case MCP2221_I2C_RD_RPT_START:
|
|
switch (data[1]) {
|
|
case MCP2221_SUCCESS:
|
|
mcp->status = 0;
|
|
break;
|
|
default:
|
|
mcp->status = mcp_get_i2c_eng_state(mcp, data, 2);
|
|
}
|
|
complete(&mcp->wait_in_report);
|
|
break;
|
|
|
|
case MCP2221_I2C_PARAM_OR_STATUS:
|
|
switch (data[1]) {
|
|
case MCP2221_SUCCESS:
|
|
if ((mcp->txbuf[3] == MCP2221_I2C_SET_SPEED) &&
|
|
(data[3] != MCP2221_I2C_SET_SPEED)) {
|
|
mcp->status = -EAGAIN;
|
|
break;
|
|
}
|
|
if (data[20] & MCP2221_I2C_MASK_ADDR_NACK) {
|
|
mcp->status = -ENXIO;
|
|
break;
|
|
}
|
|
mcp->status = mcp_get_i2c_eng_state(mcp, data, 8);
|
|
#if IS_REACHABLE(CONFIG_IIO)
|
|
memcpy(&mcp->adc_values, &data[50], sizeof(mcp->adc_values));
|
|
#endif
|
|
break;
|
|
default:
|
|
mcp->status = -EIO;
|
|
}
|
|
complete(&mcp->wait_in_report);
|
|
break;
|
|
|
|
case MCP2221_I2C_GET_DATA:
|
|
switch (data[1]) {
|
|
case MCP2221_SUCCESS:
|
|
if (data[2] == MCP2221_I2C_ADDR_NACK) {
|
|
mcp->status = -ENXIO;
|
|
break;
|
|
}
|
|
if (!mcp_get_i2c_eng_state(mcp, data, 2)
|
|
&& (data[3] == 0)) {
|
|
mcp->status = 0;
|
|
break;
|
|
}
|
|
if (data[3] == 127) {
|
|
mcp->status = -EIO;
|
|
break;
|
|
}
|
|
if (data[2] == MCP2221_I2C_READ_COMPL) {
|
|
buf = mcp->rxbuf;
|
|
memcpy(&buf[mcp->rxbuf_idx], &data[4], data[3]);
|
|
mcp->rxbuf_idx = mcp->rxbuf_idx + data[3];
|
|
mcp->status = 0;
|
|
break;
|
|
}
|
|
mcp->status = -EIO;
|
|
break;
|
|
default:
|
|
mcp->status = -EIO;
|
|
}
|
|
complete(&mcp->wait_in_report);
|
|
break;
|
|
|
|
case MCP2221_GPIO_GET:
|
|
switch (data[1]) {
|
|
case MCP2221_SUCCESS:
|
|
if ((data[mcp->gp_idx] == MCP2221_ALT_F_NOT_GPIOV) ||
|
|
(data[mcp->gp_idx + 1] == MCP2221_ALT_F_NOT_GPIOD)) {
|
|
mcp->status = -ENOENT;
|
|
} else {
|
|
mcp->status = !!data[mcp->gp_idx];
|
|
mcp->gpio_dir = data[mcp->gp_idx + 1];
|
|
}
|
|
break;
|
|
default:
|
|
mcp->status = -EAGAIN;
|
|
}
|
|
complete(&mcp->wait_in_report);
|
|
break;
|
|
|
|
case MCP2221_GPIO_SET:
|
|
switch (data[1]) {
|
|
case MCP2221_SUCCESS:
|
|
if ((data[mcp->gp_idx] == MCP2221_ALT_F_NOT_GPIOV) ||
|
|
(data[mcp->gp_idx - 1] == MCP2221_ALT_F_NOT_GPIOV)) {
|
|
mcp->status = -ENOENT;
|
|
} else {
|
|
mcp->status = 0;
|
|
}
|
|
break;
|
|
default:
|
|
mcp->status = -EAGAIN;
|
|
}
|
|
complete(&mcp->wait_in_report);
|
|
break;
|
|
|
|
case MCP2221_SET_SRAM_SETTINGS:
|
|
switch (data[1]) {
|
|
case MCP2221_SUCCESS:
|
|
mcp->status = 0;
|
|
break;
|
|
default:
|
|
mcp->status = -EAGAIN;
|
|
}
|
|
complete(&mcp->wait_in_report);
|
|
break;
|
|
|
|
case MCP2221_GET_SRAM_SETTINGS:
|
|
switch (data[1]) {
|
|
case MCP2221_SUCCESS:
|
|
memcpy(&mcp->mode, &data[22], 4);
|
|
#if IS_REACHABLE(CONFIG_IIO)
|
|
mcp->dac_value = data[6] & GENMASK(4, 0);
|
|
#endif
|
|
mcp->status = 0;
|
|
break;
|
|
default:
|
|
mcp->status = -EAGAIN;
|
|
}
|
|
complete(&mcp->wait_in_report);
|
|
break;
|
|
|
|
case MCP2221_READ_FLASH_DATA:
|
|
switch (data[1]) {
|
|
case MCP2221_SUCCESS:
|
|
mcp->status = 0;
|
|
|
|
/* Only handles CHIP SETTINGS subpage currently */
|
|
if (mcp->txbuf[1] != 0) {
|
|
mcp->status = -EIO;
|
|
break;
|
|
}
|
|
|
|
#if IS_REACHABLE(CONFIG_IIO)
|
|
{
|
|
u8 tmp;
|
|
/* DAC scale value */
|
|
tmp = FIELD_GET(GENMASK(7, 6), data[6]);
|
|
if ((data[6] & BIT(5)) && tmp)
|
|
mcp->dac_scale = tmp + 4;
|
|
else
|
|
mcp->dac_scale = 5;
|
|
|
|
/* ADC scale value */
|
|
tmp = FIELD_GET(GENMASK(4, 3), data[7]);
|
|
if ((data[7] & BIT(2)) && tmp)
|
|
mcp->adc_scale = tmp - 1;
|
|
else
|
|
mcp->adc_scale = 0;
|
|
}
|
|
#endif
|
|
|
|
break;
|
|
default:
|
|
mcp->status = -EAGAIN;
|
|
}
|
|
complete(&mcp->wait_in_report);
|
|
break;
|
|
|
|
default:
|
|
mcp->status = -EIO;
|
|
complete(&mcp->wait_in_report);
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
/* Device resource managed function for HID unregistration */
|
|
static void mcp2221_hid_unregister(void *ptr)
|
|
{
|
|
struct hid_device *hdev = ptr;
|
|
|
|
hid_hw_close(hdev);
|
|
hid_hw_stop(hdev);
|
|
}
|
|
|
|
/* This is needed to be sure hid_hw_stop() isn't called twice by the subsystem */
|
|
static void mcp2221_remove(struct hid_device *hdev)
|
|
{
|
|
struct mcp2221 *mcp = hid_get_drvdata(hdev);
|
|
|
|
cancel_delayed_work_sync(&mcp->init_work);
|
|
}
|
|
|
|
#if IS_REACHABLE(CONFIG_IIO)
|
|
static int mcp2221_read_raw(struct iio_dev *indio_dev,
|
|
struct iio_chan_spec const *channel, int *val,
|
|
int *val2, long mask)
|
|
{
|
|
struct mcp2221_iio *priv = iio_priv(indio_dev);
|
|
struct mcp2221 *mcp = priv->mcp;
|
|
int ret;
|
|
|
|
if (mask == IIO_CHAN_INFO_SCALE) {
|
|
if (channel->output)
|
|
*val = 1 << mcp->dac_scale;
|
|
else
|
|
*val = 1 << mcp->adc_scale;
|
|
|
|
return IIO_VAL_INT;
|
|
}
|
|
|
|
mutex_lock(&mcp->lock);
|
|
|
|
if (channel->output) {
|
|
*val = mcp->dac_value;
|
|
ret = IIO_VAL_INT;
|
|
} else {
|
|
/* Read ADC values */
|
|
ret = mcp_chk_last_cmd_status(mcp);
|
|
|
|
if (!ret) {
|
|
*val = le16_to_cpu((__force __le16) mcp->adc_values[channel->address]);
|
|
if (*val >= BIT(10))
|
|
ret = -EINVAL;
|
|
else
|
|
ret = IIO_VAL_INT;
|
|
}
|
|
}
|
|
|
|
mutex_unlock(&mcp->lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int mcp2221_write_raw(struct iio_dev *indio_dev,
|
|
struct iio_chan_spec const *chan,
|
|
int val, int val2, long mask)
|
|
{
|
|
struct mcp2221_iio *priv = iio_priv(indio_dev);
|
|
struct mcp2221 *mcp = priv->mcp;
|
|
int ret;
|
|
|
|
if (val < 0 || val >= BIT(5))
|
|
return -EINVAL;
|
|
|
|
mutex_lock(&mcp->lock);
|
|
|
|
memset(mcp->txbuf, 0, 12);
|
|
mcp->txbuf[0] = MCP2221_SET_SRAM_SETTINGS;
|
|
mcp->txbuf[4] = BIT(7) | val;
|
|
|
|
ret = mcp_send_data_req_status(mcp, mcp->txbuf, 12);
|
|
if (!ret)
|
|
mcp->dac_value = val;
|
|
|
|
mutex_unlock(&mcp->lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static const struct iio_info mcp2221_info = {
|
|
.read_raw = &mcp2221_read_raw,
|
|
.write_raw = &mcp2221_write_raw,
|
|
};
|
|
|
|
static int mcp_iio_channels(struct mcp2221 *mcp)
|
|
{
|
|
int idx, cnt = 0;
|
|
bool dac_created = false;
|
|
|
|
/* GP0 doesn't have ADC/DAC alternative function */
|
|
for (idx = 1; idx < MCP_NGPIO; idx++) {
|
|
struct iio_chan_spec *chan = &mcp->iio_channels[cnt];
|
|
|
|
switch (mcp->mode[idx]) {
|
|
case 2:
|
|
chan->address = idx - 1;
|
|
chan->channel = cnt++;
|
|
break;
|
|
case 3:
|
|
/* GP1 doesn't have DAC alternative function */
|
|
if (idx == 1 || dac_created)
|
|
continue;
|
|
/* DAC1 and DAC2 outputs are connected to the same DAC */
|
|
dac_created = true;
|
|
chan->output = 1;
|
|
cnt++;
|
|
break;
|
|
default:
|
|
continue;
|
|
};
|
|
|
|
chan->type = IIO_VOLTAGE;
|
|
chan->indexed = 1;
|
|
chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW);
|
|
chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE);
|
|
chan->scan_index = -1;
|
|
}
|
|
|
|
return cnt;
|
|
}
|
|
|
|
static void mcp_init_work(struct work_struct *work)
|
|
{
|
|
struct iio_dev *indio_dev;
|
|
struct mcp2221 *mcp = container_of(work, struct mcp2221, init_work.work);
|
|
struct mcp2221_iio *data;
|
|
static int retries = 5;
|
|
int ret, num_channels;
|
|
|
|
hid_hw_power(mcp->hdev, PM_HINT_FULLON);
|
|
mutex_lock(&mcp->lock);
|
|
|
|
mcp->txbuf[0] = MCP2221_GET_SRAM_SETTINGS;
|
|
ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1);
|
|
|
|
if (ret == -EAGAIN)
|
|
goto reschedule_task;
|
|
|
|
num_channels = mcp_iio_channels(mcp);
|
|
if (!num_channels)
|
|
goto unlock;
|
|
|
|
mcp->txbuf[0] = MCP2221_READ_FLASH_DATA;
|
|
mcp->txbuf[1] = 0;
|
|
ret = mcp_send_data_req_status(mcp, mcp->txbuf, 2);
|
|
|
|
if (ret == -EAGAIN)
|
|
goto reschedule_task;
|
|
|
|
indio_dev = devm_iio_device_alloc(&mcp->hdev->dev, sizeof(*data));
|
|
if (!indio_dev)
|
|
goto unlock;
|
|
|
|
data = iio_priv(indio_dev);
|
|
data->mcp = mcp;
|
|
|
|
indio_dev->name = "mcp2221";
|
|
indio_dev->modes = INDIO_DIRECT_MODE;
|
|
indio_dev->info = &mcp2221_info;
|
|
indio_dev->channels = mcp->iio_channels;
|
|
indio_dev->num_channels = num_channels;
|
|
|
|
devm_iio_device_register(&mcp->hdev->dev, indio_dev);
|
|
|
|
unlock:
|
|
mutex_unlock(&mcp->lock);
|
|
hid_hw_power(mcp->hdev, PM_HINT_NORMAL);
|
|
|
|
return;
|
|
|
|
reschedule_task:
|
|
mutex_unlock(&mcp->lock);
|
|
hid_hw_power(mcp->hdev, PM_HINT_NORMAL);
|
|
|
|
if (!retries--)
|
|
return;
|
|
|
|
/* Device is not ready to read SRAM or FLASH data, try again */
|
|
schedule_delayed_work(&mcp->init_work, msecs_to_jiffies(100));
|
|
}
|
|
#endif
|
|
|
|
static int mcp2221_probe(struct hid_device *hdev,
|
|
const struct hid_device_id *id)
|
|
{
|
|
int ret;
|
|
struct mcp2221 *mcp;
|
|
|
|
mcp = devm_kzalloc(&hdev->dev, sizeof(*mcp), GFP_KERNEL);
|
|
if (!mcp)
|
|
return -ENOMEM;
|
|
|
|
ret = hid_parse(hdev);
|
|
if (ret) {
|
|
hid_err(hdev, "can't parse reports\n");
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* This driver uses the .raw_event callback and therefore does not need any
|
|
* HID_CONNECT_xxx flags.
|
|
*/
|
|
ret = hid_hw_start(hdev, 0);
|
|
if (ret) {
|
|
hid_err(hdev, "can't start hardware\n");
|
|
return ret;
|
|
}
|
|
|
|
hid_info(hdev, "USB HID v%x.%02x Device [%s] on %s\n", hdev->version >> 8,
|
|
hdev->version & 0xff, hdev->name, hdev->phys);
|
|
|
|
ret = hid_hw_open(hdev);
|
|
if (ret) {
|
|
hid_err(hdev, "can't open device\n");
|
|
hid_hw_stop(hdev);
|
|
return ret;
|
|
}
|
|
|
|
mutex_init(&mcp->lock);
|
|
init_completion(&mcp->wait_in_report);
|
|
hid_set_drvdata(hdev, mcp);
|
|
mcp->hdev = hdev;
|
|
|
|
ret = devm_add_action_or_reset(&hdev->dev, mcp2221_hid_unregister, hdev);
|
|
if (ret)
|
|
return ret;
|
|
|
|
/* Set I2C bus clock diviser */
|
|
if (i2c_clk_freq > 400)
|
|
i2c_clk_freq = 400;
|
|
if (i2c_clk_freq < 50)
|
|
i2c_clk_freq = 50;
|
|
mcp->cur_i2c_clk_div = (12000000 / (i2c_clk_freq * 1000)) - 3;
|
|
|
|
mcp->adapter.owner = THIS_MODULE;
|
|
mcp->adapter.class = I2C_CLASS_HWMON;
|
|
mcp->adapter.algo = &mcp_i2c_algo;
|
|
mcp->adapter.retries = 1;
|
|
mcp->adapter.dev.parent = &hdev->dev;
|
|
snprintf(mcp->adapter.name, sizeof(mcp->adapter.name),
|
|
"MCP2221 usb-i2c bridge");
|
|
|
|
ret = devm_i2c_add_adapter(&hdev->dev, &mcp->adapter);
|
|
if (ret) {
|
|
hid_err(hdev, "can't add usb-i2c adapter: %d\n", ret);
|
|
return ret;
|
|
}
|
|
i2c_set_adapdata(&mcp->adapter, mcp);
|
|
|
|
#if IS_REACHABLE(CONFIG_GPIOLIB)
|
|
/* Setup GPIO chip */
|
|
mcp->gc = devm_kzalloc(&hdev->dev, sizeof(*mcp->gc), GFP_KERNEL);
|
|
if (!mcp->gc)
|
|
return -ENOMEM;
|
|
|
|
mcp->gc->label = "mcp2221_gpio";
|
|
mcp->gc->direction_input = mcp_gpio_direction_input;
|
|
mcp->gc->direction_output = mcp_gpio_direction_output;
|
|
mcp->gc->get_direction = mcp_gpio_get_direction;
|
|
mcp->gc->set = mcp_gpio_set;
|
|
mcp->gc->get = mcp_gpio_get;
|
|
mcp->gc->ngpio = MCP_NGPIO;
|
|
mcp->gc->base = -1;
|
|
mcp->gc->can_sleep = 1;
|
|
mcp->gc->parent = &hdev->dev;
|
|
|
|
ret = devm_gpiochip_add_data(&hdev->dev, mcp->gc, mcp);
|
|
if (ret)
|
|
return ret;
|
|
#endif
|
|
|
|
#if IS_REACHABLE(CONFIG_IIO)
|
|
INIT_DELAYED_WORK(&mcp->init_work, mcp_init_work);
|
|
schedule_delayed_work(&mcp->init_work, msecs_to_jiffies(100));
|
|
#endif
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct hid_device_id mcp2221_devices[] = {
|
|
{ HID_USB_DEVICE(USB_VENDOR_ID_MICROCHIP, USB_DEVICE_ID_MCP2221) },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(hid, mcp2221_devices);
|
|
|
|
static struct hid_driver mcp2221_driver = {
|
|
.name = "mcp2221",
|
|
.id_table = mcp2221_devices,
|
|
.probe = mcp2221_probe,
|
|
.remove = mcp2221_remove,
|
|
.raw_event = mcp2221_raw_event,
|
|
};
|
|
|
|
/* Register with HID core */
|
|
module_hid_driver(mcp2221_driver);
|
|
|
|
MODULE_AUTHOR("Rishi Gupta <gupt21@gmail.com>");
|
|
MODULE_DESCRIPTION("MCP2221 Microchip HID USB to I2C master bridge");
|
|
MODULE_LICENSE("GPL v2");
|