[PATCH 2/3] Input: sun4i-lradc-keys: Add optional clock/reset support
From: Samuel Holland <samuel@sholland.org>
Date: 2021-09-08 03:40:43
Also in:
linux-devicetree, linux-input, linux-sunxi, lkml
Subsystem:
input (keyboard, mouse, joystick, touchscreen) drivers, sun4i low res adc attached tablet keys driver, the rest · Maintainers:
Dmitry Torokhov, Hans de Goede, Linus Torvalds
Until the R329, the LRADC hardware was always active. Now it requires enabling a clock gate and deasserting a reset line. Do this if the clock and reset are provided in the device tree, but keep them optional to maintain support for the existing binding. Signed-off-by: Samuel Holland <samuel@sholland.org> --- drivers/input/keyboard/sun4i-lradc-keys.c | 29 +++++++++++++++++++++++ 1 file changed, 29 insertions(+)
diff --git a/drivers/input/keyboard/sun4i-lradc-keys.c b/drivers/input/keyboard/sun4i-lradc-keys.c
index 4a796bed48ac..50fc18052829 100644
--- a/drivers/input/keyboard/sun4i-lradc-keys.c
+++ b/drivers/input/keyboard/sun4i-lradc-keys.c@@ -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>
@@ -23,6 +24,7 @@ #include <linux/of_platform.h> #include <linux/platform_device.h> #include <linux/regulator/consumer.h> +#include <linux/reset.h> #include <linux/slab.h> #define LRADC_CTRL 0x00
@@ -83,6 +85,8 @@ 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;
@@ -140,6 +144,14 @@ 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;
@@ -153,6 +165,13 @@ 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)
@@ -164,6 +183,8 @@ 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); }
@@ -243,6 +264,14 @@ static int sun4i_lradc_probe(struct platform_device *pdev) return -EINVAL; } + lradc->clk = devm_clk_get_optional(dev, NULL); + if (IS_ERR(lradc->clk)) + return PTR_ERR(lradc->clk); + + lradc->reset = devm_reset_control_get_optional_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);
--
2.31.1
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