The ASPEED SoC must deassert a reset in order to use the PWM/tach peripheral.
Signed-off-by: Joel Stanley <[email protected]> --- v2: - Correct horrible mistakes - Boot tested and hwmon sysfs files checked --- drivers/hwmon/aspeed-pwm-tacho.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/drivers/hwmon/aspeed-pwm-tacho.c b/drivers/hwmon/aspeed-pwm-tacho.c index 63a95e23ca81..77bb7a4bbed4 100644 --- a/drivers/hwmon/aspeed-pwm-tacho.c +++ b/drivers/hwmon/aspeed-pwm-tacho.c @@ -19,6 +19,7 @@ #include <linux/of_platform.h> #include <linux/platform_device.h> #include <linux/regmap.h> +#include <linux/reset.h> #include <linux/sysfs.h> #include <linux/thermal.h> @@ -181,6 +182,7 @@ struct aspeed_cooling_device { struct aspeed_pwm_tacho_data { struct regmap *regmap; + struct reset_control *rst; unsigned long clk_freq; bool pwm_present[8]; bool fan_tach_present[16]; @@ -931,6 +933,15 @@ static int aspeed_pwm_tacho_probe(struct platform_device *pdev) &aspeed_pwm_tacho_regmap_config); if (IS_ERR(priv->regmap)) return PTR_ERR(priv->regmap); + + priv->rst = devm_reset_control_get_exclusive(dev, NULL); + if (IS_ERR(priv->rst)) { + dev_err(dev, + "missing or invalid reset controller device tree entry"); + return PTR_ERR(priv->rst); + } + reset_control_deassert(priv->rst); + regmap_write(priv->regmap, ASPEED_PTCR_TACH_SOURCE, 0); regmap_write(priv->regmap, ASPEED_PTCR_TACH_SOURCE_EXT, 0); @@ -960,6 +971,15 @@ static int aspeed_pwm_tacho_probe(struct platform_device *pdev) return PTR_ERR_OR_ZERO(hwmon); } +static int aspeed_pwm_tacho_remove(struct platform_device *pdev) +{ + struct aspeed_pwm_tacho_data *priv = platform_get_drvdata(pdev); + + reset_control_assert(priv->rst); + + return 0; +} + static const struct of_device_id of_pwm_tacho_match_table[] = { { .compatible = "aspeed,ast2400-pwm-tacho", }, { .compatible = "aspeed,ast2500-pwm-tacho", }, @@ -969,6 +989,7 @@ MODULE_DEVICE_TABLE(of, of_pwm_tacho_match_table); static struct platform_driver aspeed_pwm_tacho_driver = { .probe = aspeed_pwm_tacho_probe, + .remove = aspeed_pwm_tacho_remove, .driver = { .name = "aspeed_pwm_tacho", .of_match_table = of_pwm_tacho_match_table, -- 2.14.1
