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Input: sun4i-lradc-keys - add optional clock/reset support

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Until the R329, the LRADC hardware was always active. Now it requires
enabling a clock gate and deasserting a reset line. Add support for this
variant of the hardware.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Link: https://lore.kernel.org/r/20220414002349.24332-2-samuel@sholland.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
This commit is contained in:
Samuel Holland 2022-04-24 20:39:11 -07:00 committed by Dmitry Torokhov
parent 61f19f6749
commit ac2d5b43ea
1 changed files with 33 additions and 0 deletions
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33
drivers/input/keyboard/sun4i-lradc-keys.c
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@ -14,6 +14,7 @@
* there are no boards known to use channel 1.
*/
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/input.h>
@ -25,6 +26,7 @@
#include <linux/pm_wakeirq.h>
#include <linux/pm_wakeup.h>
#include <linux/regulator/consumer.h>
#include <linux/reset.h>
#include <linux/slab.h>
#define LRADC_CTRL 0x00
@ -60,10 +62,12 @@
/* struct lradc_variant - Describe sun4i-a10-lradc-keys hardware variant
* @divisor_numerator: The numerator of lradc Vref internally divisor
* @divisor_denominator: The denominator of lradc Vref internally divisor
* @has_clock_reset: If the binding requires a clock and reset
*/
struct lradc_variant {
u8 divisor_numerator;
u8 divisor_denominator;
bool has_clock_reset;
};
static const struct lradc_variant lradc_variant_a10 = {
@ -85,6 +89,8 @@ struct sun4i_lradc_data {
struct device *dev;
struct input_dev *input;
void __iomem *base;
struct clk *clk;
struct reset_control *reset;
struct regulator *vref_supply;
struct sun4i_lradc_keymap *chan0_map;
const struct lradc_variant *variant;
@ -142,6 +148,14 @@ static int sun4i_lradc_open(struct input_dev *dev)
if (error)
return error;
error = reset_control_deassert(lradc->reset);
if (error)
goto err_disable_reg;
error = clk_prepare_enable(lradc->clk);
if (error)
goto err_assert_reset;
lradc->vref = regulator_get_voltage(lradc->vref_supply) *
lradc->variant->divisor_numerator /
lradc->variant->divisor_denominator;
@ -155,6 +169,13 @@ static int sun4i_lradc_open(struct input_dev *dev)
writel(CHAN0_KEYUP_IRQ | CHAN0_KEYDOWN_IRQ, lradc->base + LRADC_INTC);
return 0;
err_assert_reset:
reset_control_assert(lradc->reset);
err_disable_reg:
regulator_disable(lradc->vref_supply);
return error;
}
static void sun4i_lradc_close(struct input_dev *dev)
@ -166,6 +187,8 @@ static void sun4i_lradc_close(struct input_dev *dev)
SAMPLE_RATE(2), lradc->base + LRADC_CTRL);
writel(0, lradc->base + LRADC_INTC);
clk_disable_unprepare(lradc->clk);
reset_control_assert(lradc->reset);
regulator_disable(lradc->vref_supply);
}
@ -244,6 +267,16 @@ static int sun4i_lradc_probe(struct platform_device *pdev)
return -EINVAL;
}
if (lradc->variant->has_clock_reset) {
lradc->clk = devm_clk_get(dev, NULL);
if (IS_ERR(lradc->clk))
return PTR_ERR(lradc->clk);
lradc->reset = devm_reset_control_get_exclusive(dev, NULL);
if (IS_ERR(lradc->reset))
return PTR_ERR(lradc->reset);
}
lradc->vref_supply = devm_regulator_get(dev, "vref");
if (IS_ERR(lradc->vref_supply))
return PTR_ERR(lradc->vref_supply);