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i2c: pxa: move to generic GPIO recovery

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commit 75820314de ("i2c: core: add generic I2C GPIO recovery")
GPIO bus recovery is supported by the I2C core, so we can remove the
driver implementation and use that one instead.

Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
This commit is contained in:
Codrin Ciubotariu 2020-10-04 13:07:11 +03:00 committed by Wolfram Sang
parent e8a61e5a7e
commit 0b01392c18
1 changed files with 8 additions and 68 deletions
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76
drivers/i2c/busses/i2c-pxa.c
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@ -264,9 +264,6 @@ struct pxa_i2c {
u32 hs_mask;
struct i2c_bus_recovery_info recovery;
struct pinctrl *pinctrl;
struct pinctrl_state *pinctrl_default;
struct pinctrl_state *pinctrl_recovery;
};
#define _IBMR(i2c) ((i2c)->reg_ibmr)
@ -1305,13 +1302,12 @@ static void i2c_pxa_prepare_recovery(struct i2c_adapter *adap)
*/
gpiod_set_value(i2c->recovery.scl_gpiod, ibmr & IBMR_SCLS);
gpiod_set_value(i2c->recovery.sda_gpiod, ibmr & IBMR_SDAS);
WARN_ON(pinctrl_select_state(i2c->pinctrl, i2c->pinctrl_recovery));
}
static void i2c_pxa_unprepare_recovery(struct i2c_adapter *adap)
{
struct pxa_i2c *i2c = adap->algo_data;
struct i2c_bus_recovery_info *bri = adap->bus_recovery_info;
u32 isr;
/*
@ -1325,7 +1321,7 @@ static void i2c_pxa_unprepare_recovery(struct i2c_adapter *adap)
i2c_pxa_do_reset(i2c);
}
WARN_ON(pinctrl_select_state(i2c->pinctrl, i2c->pinctrl_default));
WARN_ON(pinctrl_select_state(bri->pinctrl, bri->pins_default));
dev_dbg(&i2c->adap.dev, "recovery: IBMR 0x%08x ISR 0x%08x\n",
readl(_IBMR(i2c)), readl(_ISR(i2c)));
@ -1347,76 +1343,20 @@ static int i2c_pxa_init_recovery(struct pxa_i2c *i2c)
if (IS_ENABLED(CONFIG_I2C_PXA_SLAVE))
return 0;
i2c->pinctrl = devm_pinctrl_get(dev);
if (PTR_ERR(i2c->pinctrl) == -ENODEV)
i2c->pinctrl = NULL;
if (IS_ERR(i2c->pinctrl))
return PTR_ERR(i2c->pinctrl);
if (!i2c->pinctrl)
return 0;
i2c->pinctrl_default = pinctrl_lookup_state(i2c->pinctrl,
PINCTRL_STATE_DEFAULT);
i2c->pinctrl_recovery = pinctrl_lookup_state(i2c->pinctrl, "recovery");
if (IS_ERR(i2c->pinctrl_default) || IS_ERR(i2c->pinctrl_recovery)) {
dev_info(dev, "missing pinmux recovery information: %ld %ld\n",
PTR_ERR(i2c->pinctrl_default),
PTR_ERR(i2c->pinctrl_recovery));
return 0;
}
/*
* Claiming GPIOs can influence the pinmux state, and may glitch the
* I2C bus. Do this carefully.
*/
bri->scl_gpiod = devm_gpiod_get(dev, "scl", GPIOD_OUT_HIGH_OPEN_DRAIN);
if (bri->scl_gpiod == ERR_PTR(-EPROBE_DEFER))
return -EPROBE_DEFER;
if (IS_ERR(bri->scl_gpiod)) {
dev_info(dev, "missing scl gpio recovery information: %pe\n",
bri->scl_gpiod);
return 0;
}
/*
* We have SCL. Pull SCL low and wait a bit so that SDA glitches
* have no effect.
*/
gpiod_direction_output(bri->scl_gpiod, 0);
udelay(10);
bri->sda_gpiod = devm_gpiod_get(dev, "sda", GPIOD_OUT_HIGH_OPEN_DRAIN);
/* Wait a bit in case of a SDA glitch, and then release SCL. */
udelay(10);
gpiod_direction_output(bri->scl_gpiod, 1);
if (bri->sda_gpiod == ERR_PTR(-EPROBE_DEFER))
return -EPROBE_DEFER;
if (IS_ERR(bri->sda_gpiod)) {
dev_info(dev, "missing sda gpio recovery information: %pe\n",
bri->sda_gpiod);
bri->pinctrl = devm_pinctrl_get(dev);
if (PTR_ERR(bri->pinctrl) == -ENODEV) {
bri->pinctrl = NULL;
return 0;
}
if (IS_ERR(bri->pinctrl))
return PTR_ERR(bri->pinctrl);
bri->prepare_recovery = i2c_pxa_prepare_recovery;
bri->unprepare_recovery = i2c_pxa_unprepare_recovery;
bri->recover_bus = i2c_generic_scl_recovery;
i2c->adap.bus_recovery_info = bri;
/*
* Claiming GPIOs can change the pinmux state, which confuses the
* pinctrl since pinctrl's idea of the current setting is unaffected
* by the pinmux change caused by claiming the GPIO. Work around that
* by switching pinctrl to the GPIO state here. We do it this way to
* avoid glitching the I2C bus.
*/
pinctrl_select_state(i2c->pinctrl, i2c->pinctrl_recovery);
return pinctrl_select_state(i2c->pinctrl, i2c->pinctrl_default);
return 0;
}
static int i2c_pxa_probe(struct platform_device *dev)