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i2c/ARM: davinci: Deep refactoring of I2C recovery
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Alter the DaVinci GPIO recovery fetch to use descriptors
all the way down into the board files.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Sekhar Nori <nsekhar@ti.com>
Tested-by: Sekhar Nori <nsekhar@ti.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Linus Walleij authored and Wolfram Sang committed Dec 30, 2017
1 parent 7d42762 commit e535376
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Showing 4 changed files with 39 additions and 17 deletions.
15 changes: 13 additions & 2 deletions arch/arm/mach-davinci/board-dm355-evm.c
Original file line number Diff line number Diff line change
Expand Up @@ -17,6 +17,7 @@
#include <linux/mtd/rawnand.h>
#include <linux/i2c.h>
#include <linux/gpio.h>
#include <linux/gpio/machine.h>
#include <linux/clk.h>
#include <linux/videodev2.h>
#include <media/i2c/tvp514x.h>
Expand Down Expand Up @@ -108,11 +109,20 @@ static struct platform_device davinci_nand_device = {
},
};

static struct gpiod_lookup_table i2c_recovery_gpiod_table = {
.dev_id = "i2c_davinci",
.table = {
GPIO_LOOKUP("davinci_gpio", 15, "sda",
GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN),
GPIO_LOOKUP("davinci_gpio", 14, "scl",
GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN),
},
};

static struct davinci_i2c_platform_data i2c_pdata = {
.bus_freq = 400 /* kHz */,
.bus_delay = 0 /* usec */,
.sda_pin = 15,
.scl_pin = 14,
.gpio_recovery = true,
};

static int dm355evm_mmc_gpios = -EINVAL;
Expand Down Expand Up @@ -141,6 +151,7 @@ static struct i2c_board_info dm355evm_i2c_info[] = {

static void __init evm_init_i2c(void)
{
gpiod_add_lookup_table(&i2c_recovery_gpiod_table);
davinci_init_i2c(&i2c_pdata);

gpio_request(5, "dm355evm_msp");
Expand Down
15 changes: 13 additions & 2 deletions arch/arm/mach-davinci/board-dm644x-evm.c
Original file line number Diff line number Diff line change
Expand Up @@ -13,6 +13,7 @@
#include <linux/dma-mapping.h>
#include <linux/platform_device.h>
#include <linux/gpio.h>
#include <linux/gpio/machine.h>
#include <linux/i2c.h>
#include <linux/platform_data/pcf857x.h>
#include <linux/platform_data/at24.h>
Expand Down Expand Up @@ -595,18 +596,28 @@ static struct i2c_board_info __initdata i2c_info[] = {
},
};

static struct gpiod_lookup_table i2c_recovery_gpiod_table = {
.dev_id = "i2c_davinci",
.table = {
GPIO_LOOKUP("davinci_gpio", 44, "sda",
GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN),
GPIO_LOOKUP("davinci_gpio", 43, "scl",
GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN),
},
};

/* The msp430 uses a slow bitbanged I2C implementation (ergo 20 KHz),
* which requires 100 usec of idle bus after i2c writes sent to it.
*/
static struct davinci_i2c_platform_data i2c_pdata = {
.bus_freq = 20 /* kHz */,
.bus_delay = 100 /* usec */,
.sda_pin = 44,
.scl_pin = 43,
.gpio_recovery = true,
};

static void __init evm_init_i2c(void)
{
gpiod_add_lookup_table(&i2c_recovery_gpiod_table);
davinci_init_i2c(&i2c_pdata);
i2c_add_driver(&dm6446evm_msp_driver);
i2c_register_board_info(1, i2c_info, ARRAY_SIZE(i2c_info));
Expand Down
21 changes: 11 additions & 10 deletions drivers/i2c/busses/i2c-davinci.c
Original file line number Diff line number Diff line change
Expand Up @@ -33,7 +33,7 @@
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/cpufreq.h>
#include <linux/gpio.h>
#include <linux/gpio/consumer.h>
#include <linux/of_device.h>
#include <linux/platform_data/i2c-davinci.h>
#include <linux/pm_runtime.h>
Expand Down Expand Up @@ -869,19 +869,20 @@ static int davinci_i2c_probe(struct platform_device *pdev)

if (dev->pdata->has_pfunc)
adap->bus_recovery_info = &davinci_i2c_scl_recovery_info;
else if (dev->pdata->scl_pin) {
else if (dev->pdata->gpio_recovery) {
rinfo = &davinci_i2c_gpio_recovery_info;
adap->bus_recovery_info = rinfo;
r = gpio_request_one(dev->pdata->scl_pin, GPIOF_OPEN_DRAIN |
GPIOF_OUT_INIT_HIGH, "i2c-scl");
if (r)
rinfo->scl_gpiod = devm_gpiod_get(&pdev->dev, "scl",
GPIOD_OUT_HIGH_OPEN_DRAIN);
if (IS_ERR(rinfo->scl_gpiod)) {
r = PTR_ERR(rinfo->scl_gpiod);
goto err_unuse_clocks;
rinfo->scl_gpiod = gpio_to_desc(dev->pdata->scl_pin);

r = gpio_request_one(dev->pdata->sda_pin, GPIOF_IN, "i2c-sda");
if (r)
}
rinfo->sda_gpiod = devm_gpiod_get(&pdev->dev, "sda", GPIOD_IN);
if (IS_ERR(rinfo->sda_gpiod)) {
r = PTR_ERR(rinfo->sda_gpiod);
goto err_unuse_clocks;
rinfo->sda_gpiod = gpio_to_desc(dev->pdata->scl_pin);
}
}

adap->nr = pdev->id;
Expand Down
5 changes: 2 additions & 3 deletions include/linux/platform_data/i2c-davinci.h
Original file line number Diff line number Diff line change
Expand Up @@ -16,9 +16,8 @@
struct davinci_i2c_platform_data {
unsigned int bus_freq; /* standard bus frequency (kHz) */
unsigned int bus_delay; /* post-transaction delay (usec) */
unsigned int sda_pin; /* GPIO pin ID to use for SDA */
unsigned int scl_pin; /* GPIO pin ID to use for SCL */
bool has_pfunc; /*chip has a ICPFUNC register */
bool gpio_recovery; /* Use GPIO recovery method */
bool has_pfunc; /* Chip has a ICPFUNC register */
};

/* for board setup code */
Expand Down

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