[RFC PATCH 4/4] i2c: at91: Move to generic GPIO bus recovery

From: Codrin Ciubotariu
Date: Fri Jun 19 2020 - 10:22:03 EST


Make the Microchip at91 driver the first to use the generic GPIO bus
recovery support from the I2C core and discard the driver implementation.

Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@xxxxxxxxxxxxx>
---
drivers/i2c/busses/i2c-at91-master.c | 69 ++--------------------------
drivers/i2c/busses/i2c-at91.h | 3 --
2 files changed, 3 insertions(+), 69 deletions(-)

diff --git a/drivers/i2c/busses/i2c-at91-master.c b/drivers/i2c/busses/i2c-at91-master.c
index 363d540a8345..66864f9cf7ac 100644
--- a/drivers/i2c/busses/i2c-at91-master.c
+++ b/drivers/i2c/busses/i2c-at91-master.c
@@ -816,79 +816,16 @@ static int at91_twi_configure_dma(struct at91_twi_dev *dev, u32 phy_addr)
return ret;
}

-static void at91_prepare_twi_recovery(struct i2c_adapter *adap)
-{
- struct at91_twi_dev *dev = i2c_get_adapdata(adap);
-
- pinctrl_select_state(dev->pinctrl, dev->pinctrl_pins_gpio);
-}
-
-static void at91_unprepare_twi_recovery(struct i2c_adapter *adap)
-{
- struct at91_twi_dev *dev = i2c_get_adapdata(adap);
-
- pinctrl_select_state(dev->pinctrl, dev->pinctrl_pins_default);
-}
-
static int at91_init_twi_recovery_gpio(struct platform_device *pdev,
struct at91_twi_dev *dev)
{
struct i2c_bus_recovery_info *rinfo = &dev->rinfo;

- dev->pinctrl = devm_pinctrl_get(&pdev->dev);
- if (!dev->pinctrl || IS_ERR(dev->pinctrl)) {
+ rinfo->pinctrl = devm_pinctrl_get(&pdev->dev);
+ if (!rinfo->pinctrl || IS_ERR(rinfo->pinctrl)) {
dev_info(dev->dev, "can't get pinctrl, bus recovery not supported\n");
- return PTR_ERR(dev->pinctrl);
+ return PTR_ERR(rinfo->pinctrl);
}
-
- dev->pinctrl_pins_default = pinctrl_lookup_state(dev->pinctrl,
- PINCTRL_STATE_DEFAULT);
- dev->pinctrl_pins_gpio = pinctrl_lookup_state(dev->pinctrl,
- "gpio");
- if (IS_ERR(dev->pinctrl_pins_default) ||
- IS_ERR(dev->pinctrl_pins_gpio)) {
- dev_info(&pdev->dev, "pinctrl states incomplete for recovery\n");
- return -EINVAL;
- }
-
- /*
- * pins will be taken as GPIO, so we might as well inform pinctrl about
- * this and move the state to GPIO
- */
- pinctrl_select_state(dev->pinctrl, dev->pinctrl_pins_gpio);
-
- rinfo->sda_gpiod = devm_gpiod_get(&pdev->dev, "sda", GPIOD_IN);
- if (PTR_ERR(rinfo->sda_gpiod) == -EPROBE_DEFER)
- return -EPROBE_DEFER;
-
- rinfo->scl_gpiod = devm_gpiod_get(&pdev->dev, "scl",
- GPIOD_OUT_HIGH_OPEN_DRAIN);
- if (PTR_ERR(rinfo->scl_gpiod) == -EPROBE_DEFER)
- return -EPROBE_DEFER;
-
- if (IS_ERR(rinfo->sda_gpiod) ||
- IS_ERR(rinfo->scl_gpiod)) {
- dev_info(&pdev->dev, "recovery information incomplete\n");
- if (!IS_ERR(rinfo->sda_gpiod)) {
- gpiod_put(rinfo->sda_gpiod);
- rinfo->sda_gpiod = NULL;
- }
- if (!IS_ERR(rinfo->scl_gpiod)) {
- gpiod_put(rinfo->scl_gpiod);
- rinfo->scl_gpiod = NULL;
- }
- pinctrl_select_state(dev->pinctrl, dev->pinctrl_pins_default);
- return -EINVAL;
- }
-
- /* change the state of the pins back to their default state */
- pinctrl_select_state(dev->pinctrl, dev->pinctrl_pins_default);
-
- dev_info(&pdev->dev, "using scl, sda for recovery\n");
-
- rinfo->prepare_recovery = at91_prepare_twi_recovery;
- rinfo->unprepare_recovery = at91_unprepare_twi_recovery;
- rinfo->recover_bus = i2c_generic_scl_recovery;
dev->adapter.bus_recovery_info = rinfo;

return 0;
diff --git a/drivers/i2c/busses/i2c-at91.h b/drivers/i2c/busses/i2c-at91.h
index 7e7b4955ca7f..eae673ae786c 100644
--- a/drivers/i2c/busses/i2c-at91.h
+++ b/drivers/i2c/busses/i2c-at91.h
@@ -157,9 +157,6 @@ struct at91_twi_dev {
struct at91_twi_dma dma;
bool slave_detected;
struct i2c_bus_recovery_info rinfo;
- struct pinctrl *pinctrl;
- struct pinctrl_state *pinctrl_pins_default;
- struct pinctrl_state *pinctrl_pins_gpio;
#ifdef CONFIG_I2C_AT91_SLAVE_EXPERIMENTAL
unsigned smr;
struct i2c_client *slave;
--
2.25.1