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linux-stable/drivers/spi/spi-amd.c
Amit Kumar Mahapatra via Alsa-devel 9e264f3f85
spi: Replace all spi->chip_select and spi->cs_gpiod references with function call 
Supporting multi-cs in spi drivers would require the chip_select & cs_gpiod
members of struct spi_device to be an array. But changing the type of these
members to array would break the spi driver functionality. To make the
transition smoother introduced four new APIs to get/set the
spi->chip_select & spi->cs_gpiod and replaced all spi->chip_select and
spi->cs_gpiod references with get or set API calls.
While adding multi-cs support in further patches the chip_select & cs_gpiod
members of the spi_device structure would be converted to arrays & the
"idx" parameter of the APIs would be used as array index i.e.,
spi->chip_select[idx] & spi->cs_gpiod[idx] respectively.

Signed-off-by: Amit Kumar Mahapatra <amit.kumar-mahapatra@amd.com>
Acked-by: Heiko Stuebner <heiko@sntech.de> # Rockchip drivers
Reviewed-by: Michal Simek <michal.simek@amd.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org> # Aspeed driver
Reviewed-by: Dhruva Gole <d-gole@ti.com> # SPI Cadence QSPI
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com> # spi-stm32-qspi
Acked-by: William Zhang <william.zhang@broadcom.com> # bcm63xx-hsspi driver
Reviewed-by: Serge Semin <fancer.lancer@gmail.com> # DW SSI part
Link: https://lore.kernel.org/r/167847070432.26.15076794204368669839@mailman-core.alsa-project.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-03-11 12:34:01 +00:00

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// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
//
// AMD SPI controller driver
//
// Copyright (c) 2020, Advanced Micro Devices, Inc.
//
// Author: Sanjay R Mehta <sanju.mehta@amd.com>
#include <linux/acpi.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/delay.h>
#include <linux/spi/spi.h>
#include <linux/iopoll.h>
#define AMD_SPI_CTRL0_REG 0x00
#define AMD_SPI_EXEC_CMD BIT(16)
#define AMD_SPI_FIFO_CLEAR BIT(20)
#define AMD_SPI_BUSY BIT(31)
#define AMD_SPI_OPCODE_REG 0x45
#define AMD_SPI_CMD_TRIGGER_REG 0x47
#define AMD_SPI_TRIGGER_CMD BIT(7)
#define AMD_SPI_OPCODE_MASK 0xFF
#define AMD_SPI_ALT_CS_REG 0x1D
#define AMD_SPI_ALT_CS_MASK 0x3
#define AMD_SPI_FIFO_BASE 0x80
#define AMD_SPI_TX_COUNT_REG 0x48
#define AMD_SPI_RX_COUNT_REG 0x4B
#define AMD_SPI_STATUS_REG 0x4C
#define AMD_SPI_FIFO_SIZE 70
#define AMD_SPI_MEM_SIZE 200
#define AMD_SPI_ENA_REG 0x20
#define AMD_SPI_ALT_SPD_SHIFT 20
#define AMD_SPI_ALT_SPD_MASK GENMASK(23, AMD_SPI_ALT_SPD_SHIFT)
#define AMD_SPI_SPI100_SHIFT 0
#define AMD_SPI_SPI100_MASK GENMASK(AMD_SPI_SPI100_SHIFT, AMD_SPI_SPI100_SHIFT)
#define AMD_SPI_SPEED_REG 0x6C
#define AMD_SPI_SPD7_SHIFT 8
#define AMD_SPI_SPD7_MASK GENMASK(13, AMD_SPI_SPD7_SHIFT)
#define AMD_SPI_MAX_HZ 100000000
#define AMD_SPI_MIN_HZ 800000
/**
* enum amd_spi_versions - SPI controller versions
* @AMD_SPI_V1: AMDI0061 hardware version
* @AMD_SPI_V2: AMDI0062 hardware version
*/
enum amd_spi_versions {
AMD_SPI_V1 = 1,
AMD_SPI_V2,
};
enum amd_spi_speed {
F_66_66MHz,
F_33_33MHz,
F_22_22MHz,
F_16_66MHz,
F_100MHz,
F_800KHz,
SPI_SPD7 = 0x7,
F_50MHz = 0x4,
F_4MHz = 0x32,
F_3_17MHz = 0x3F
};
/**
* struct amd_spi_freq - Matches device speed with values to write in regs
* @speed_hz: Device frequency
* @enable_val: Value to be written to "enable register"
* @spd7_val: Some frequencies requires to have a value written at SPISPEED register
*/
struct amd_spi_freq {
u32 speed_hz;
u32 enable_val;
u32 spd7_val;
};
/**
* struct amd_spi - SPI driver instance
* @io_remap_addr: Start address of the SPI controller registers
* @version: SPI controller hardware version
* @speed_hz: Device frequency
*/
struct amd_spi {
void __iomem *io_remap_addr;
enum amd_spi_versions version;
unsigned int speed_hz;
};
static inline u8 amd_spi_readreg8(struct amd_spi *amd_spi, int idx)
{
return ioread8((u8 __iomem *)amd_spi->io_remap_addr + idx);
}
static inline void amd_spi_writereg8(struct amd_spi *amd_spi, int idx, u8 val)
{
iowrite8(val, ((u8 __iomem *)amd_spi->io_remap_addr + idx));
}
static void amd_spi_setclear_reg8(struct amd_spi *amd_spi, int idx, u8 set, u8 clear)
{
u8 tmp = amd_spi_readreg8(amd_spi, idx);
tmp = (tmp & ~clear) | set;
amd_spi_writereg8(amd_spi, idx, tmp);
}
static inline u32 amd_spi_readreg32(struct amd_spi *amd_spi, int idx)
{
return ioread32((u8 __iomem *)amd_spi->io_remap_addr + idx);
}
static inline void amd_spi_writereg32(struct amd_spi *amd_spi, int idx, u32 val)
{
iowrite32(val, ((u8 __iomem *)amd_spi->io_remap_addr + idx));
}
static inline void amd_spi_setclear_reg32(struct amd_spi *amd_spi, int idx, u32 set, u32 clear)
{
u32 tmp = amd_spi_readreg32(amd_spi, idx);
tmp = (tmp & ~clear) | set;
amd_spi_writereg32(amd_spi, idx, tmp);
}
static void amd_spi_select_chip(struct amd_spi *amd_spi, u8 cs)
{
amd_spi_setclear_reg8(amd_spi, AMD_SPI_ALT_CS_REG, cs, AMD_SPI_ALT_CS_MASK);
}
static inline void amd_spi_clear_chip(struct amd_spi *amd_spi, u8 chip_select)
{
amd_spi_writereg8(amd_spi, AMD_SPI_ALT_CS_REG, chip_select & ~AMD_SPI_ALT_CS_MASK);
}
static void amd_spi_clear_fifo_ptr(struct amd_spi *amd_spi)
{
amd_spi_setclear_reg32(amd_spi, AMD_SPI_CTRL0_REG, AMD_SPI_FIFO_CLEAR, AMD_SPI_FIFO_CLEAR);
}
static int amd_spi_set_opcode(struct amd_spi *amd_spi, u8 cmd_opcode)
{
switch (amd_spi->version) {
case AMD_SPI_V1:
amd_spi_setclear_reg32(amd_spi, AMD_SPI_CTRL0_REG, cmd_opcode,
AMD_SPI_OPCODE_MASK);
return 0;
case AMD_SPI_V2:
amd_spi_writereg8(amd_spi, AMD_SPI_OPCODE_REG, cmd_opcode);
return 0;
default:
return -ENODEV;
}
}
static inline void amd_spi_set_rx_count(struct amd_spi *amd_spi, u8 rx_count)
{
amd_spi_setclear_reg8(amd_spi, AMD_SPI_RX_COUNT_REG, rx_count, 0xff);
}
static inline void amd_spi_set_tx_count(struct amd_spi *amd_spi, u8 tx_count)
{
amd_spi_setclear_reg8(amd_spi, AMD_SPI_TX_COUNT_REG, tx_count, 0xff);
}
static int amd_spi_busy_wait(struct amd_spi *amd_spi)
{
u32 val;
int reg;
switch (amd_spi->version) {
case AMD_SPI_V1:
reg = AMD_SPI_CTRL0_REG;
break;
case AMD_SPI_V2:
reg = AMD_SPI_STATUS_REG;
break;
default:
return -ENODEV;
}
return readl_poll_timeout(amd_spi->io_remap_addr + reg, val,
!(val & AMD_SPI_BUSY), 20, 2000000);
}
static int amd_spi_execute_opcode(struct amd_spi *amd_spi)
{
int ret;
ret = amd_spi_busy_wait(amd_spi);
if (ret)
return ret;
switch (amd_spi->version) {
case AMD_SPI_V1:
/* Set ExecuteOpCode bit in the CTRL0 register */
amd_spi_setclear_reg32(amd_spi, AMD_SPI_CTRL0_REG, AMD_SPI_EXEC_CMD,
AMD_SPI_EXEC_CMD);
return 0;
case AMD_SPI_V2:
/* Trigger the command execution */
amd_spi_setclear_reg8(amd_spi, AMD_SPI_CMD_TRIGGER_REG,
AMD_SPI_TRIGGER_CMD, AMD_SPI_TRIGGER_CMD);
return 0;
default:
return -ENODEV;
}
}
static int amd_spi_master_setup(struct spi_device *spi)
{
struct amd_spi *amd_spi = spi_master_get_devdata(spi->master);
amd_spi_clear_fifo_ptr(amd_spi);
return 0;
}
static const struct amd_spi_freq amd_spi_freq[] = {
{ AMD_SPI_MAX_HZ, F_100MHz, 0},
{ 66660000, F_66_66MHz, 0},
{ 50000000, SPI_SPD7, F_50MHz},
{ 33330000, F_33_33MHz, 0},
{ 22220000, F_22_22MHz, 0},
{ 16660000, F_16_66MHz, 0},
{ 4000000, SPI_SPD7, F_4MHz},
{ 3170000, SPI_SPD7, F_3_17MHz},
{ AMD_SPI_MIN_HZ, F_800KHz, 0},
};
static int amd_set_spi_freq(struct amd_spi *amd_spi, u32 speed_hz)
{
unsigned int i, spd7_val, alt_spd;
if (speed_hz < AMD_SPI_MIN_HZ)
return -EINVAL;
for (i = 0; i < ARRAY_SIZE(amd_spi_freq); i++)
if (speed_hz >= amd_spi_freq[i].speed_hz)
break;
if (amd_spi->speed_hz == amd_spi_freq[i].speed_hz)
return 0;
amd_spi->speed_hz = amd_spi_freq[i].speed_hz;
alt_spd = (amd_spi_freq[i].enable_val << AMD_SPI_ALT_SPD_SHIFT)
& AMD_SPI_ALT_SPD_MASK;
amd_spi_setclear_reg32(amd_spi, AMD_SPI_ENA_REG, alt_spd,
AMD_SPI_ALT_SPD_MASK);
if (amd_spi->speed_hz == AMD_SPI_MAX_HZ)
amd_spi_setclear_reg32(amd_spi, AMD_SPI_ENA_REG, 1,
AMD_SPI_SPI100_MASK);
if (amd_spi_freq[i].spd7_val) {
spd7_val = (amd_spi_freq[i].spd7_val << AMD_SPI_SPD7_SHIFT)
& AMD_SPI_SPD7_MASK;
amd_spi_setclear_reg32(amd_spi, AMD_SPI_SPEED_REG, spd7_val,
AMD_SPI_SPD7_MASK);
}
return 0;
}
static inline int amd_spi_fifo_xfer(struct amd_spi *amd_spi,
struct spi_master *master,
struct spi_message *message)
{
struct spi_transfer *xfer = NULL;
struct spi_device *spi = message->spi;
u8 cmd_opcode = 0, fifo_pos = AMD_SPI_FIFO_BASE;
u8 *buf = NULL;
u32 i = 0;
u32 tx_len = 0, rx_len = 0;
list_for_each_entry(xfer, &message->transfers,
transfer_list) {
if (xfer->speed_hz)
amd_set_spi_freq(amd_spi, xfer->speed_hz);
else
amd_set_spi_freq(amd_spi, spi->max_speed_hz);
if (xfer->tx_buf) {
buf = (u8 *)xfer->tx_buf;
if (!tx_len) {
cmd_opcode = *(u8 *)xfer->tx_buf;
buf++;
xfer->len--;
}
tx_len += xfer->len;
/* Write data into the FIFO. */
for (i = 0; i < xfer->len; i++)
amd_spi_writereg8(amd_spi, fifo_pos + i, buf[i]);
fifo_pos += xfer->len;
}
/* Store no. of bytes to be received from FIFO */
if (xfer->rx_buf)
rx_len += xfer->len;
}
if (!buf) {
message->status = -EINVAL;
goto fin_msg;
}
amd_spi_set_opcode(amd_spi, cmd_opcode);
amd_spi_set_tx_count(amd_spi, tx_len);
amd_spi_set_rx_count(amd_spi, rx_len);
/* Execute command */
message->status = amd_spi_execute_opcode(amd_spi);
if (message->status)
goto fin_msg;
if (rx_len) {
message->status = amd_spi_busy_wait(amd_spi);
if (message->status)
goto fin_msg;
list_for_each_entry(xfer, &message->transfers, transfer_list)
if (xfer->rx_buf) {
buf = (u8 *)xfer->rx_buf;
/* Read data from FIFO to receive buffer */
for (i = 0; i < xfer->len; i++)
buf[i] = amd_spi_readreg8(amd_spi, fifo_pos + i);
fifo_pos += xfer->len;
}
}
/* Update statistics */
message->actual_length = tx_len + rx_len + 1;
fin_msg:
switch (amd_spi->version) {
case AMD_SPI_V1:
break;
case AMD_SPI_V2:
amd_spi_clear_chip(amd_spi, spi_get_chipselect(message->spi, 0));
break;
default:
return -ENODEV;
}
spi_finalize_current_message(master);
return message->status;
}
static int amd_spi_master_transfer(struct spi_master *master,
struct spi_message *msg)
{
struct amd_spi *amd_spi = spi_master_get_devdata(master);
struct spi_device *spi = msg->spi;
amd_spi_select_chip(amd_spi, spi_get_chipselect(spi, 0));
/*
* Extract spi_transfers from the spi message and
* program the controller.
*/
return amd_spi_fifo_xfer(amd_spi, master, msg);
}
static size_t amd_spi_max_transfer_size(struct spi_device *spi)
{
return AMD_SPI_FIFO_SIZE;
}
static int amd_spi_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct spi_master *master;
struct amd_spi *amd_spi;
int err;
/* Allocate storage for spi_master and driver private data */
master = devm_spi_alloc_master(dev, sizeof(struct amd_spi));
if (!master)
return dev_err_probe(dev, -ENOMEM, "Error allocating SPI master\n");
amd_spi = spi_master_get_devdata(master);
amd_spi->io_remap_addr = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(amd_spi->io_remap_addr))
return dev_err_probe(dev, PTR_ERR(amd_spi->io_remap_addr),
"ioremap of SPI registers failed\n");
dev_dbg(dev, "io_remap_address: %p\n", amd_spi->io_remap_addr);
amd_spi->version = (enum amd_spi_versions) device_get_match_data(dev);
/* Initialize the spi_master fields */
master->bus_num = 0;
master->num_chipselect = 4;
master->mode_bits = 0;
master->flags = SPI_MASTER_HALF_DUPLEX;
master->max_speed_hz = AMD_SPI_MAX_HZ;
master->min_speed_hz = AMD_SPI_MIN_HZ;
master->setup = amd_spi_master_setup;
master->transfer_one_message = amd_spi_master_transfer;
master->max_transfer_size = amd_spi_max_transfer_size;
master->max_message_size = amd_spi_max_transfer_size;
/* Register the controller with SPI framework */
err = devm_spi_register_master(dev, master);
if (err)
return dev_err_probe(dev, err, "error registering SPI controller\n");
return 0;
}
#ifdef CONFIG_ACPI
static const struct acpi_device_id spi_acpi_match[] = {
{ "AMDI0061", AMD_SPI_V1 },
{ "AMDI0062", AMD_SPI_V2 },
{},
};
MODULE_DEVICE_TABLE(acpi, spi_acpi_match);
#endif
static struct platform_driver amd_spi_driver = {
.driver = {
.name = "amd_spi",
.acpi_match_table = ACPI_PTR(spi_acpi_match),
},
.probe = amd_spi_probe,
};
module_platform_driver(amd_spi_driver);
MODULE_LICENSE("Dual BSD/GPL");
MODULE_AUTHOR("Sanjay Mehta <sanju.mehta@amd.com>");
MODULE_DESCRIPTION("AMD SPI Master Controller Driver");
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