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authorJoel <joel@jms.id.au>2017-12-23 16:05:28 +0300
committerGuenter Roeck <linux@roeck-us.net>2018-01-03 02:05:34 +0300
commit18c514cc0e0278b7852a6741973a9523ad012700 (patch)
tree734dfcbba032f2149eceddeee6e00f611c661c55 /drivers/hwmon/aspeed-pwm-tacho.c
parent8c9e52705740b21c546907711630c389ef09715e (diff)
downloadlinux-18c514cc0e0278b7852a6741973a9523ad012700.tar.xz
hwmon: (aspeed-pwm-tacho) Deassert reset in probe
The ASPEED SoC must deassert a reset in order to use the PWM/tach peripheral. Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Diffstat (limited to 'drivers/hwmon/aspeed-pwm-tacho.c')
-rw-r--r--drivers/hwmon/aspeed-pwm-tacho.c22
1 files changed, 22 insertions, 0 deletions
diff --git a/drivers/hwmon/aspeed-pwm-tacho.c b/drivers/hwmon/aspeed-pwm-tacho.c
index 63a95e23ca81..693a3d53cab5 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];
@@ -905,6 +907,13 @@ static int aspeed_create_fan(struct device *dev,
return 0;
}
+static void aspeed_pwm_tacho_remove(void *data)
+{
+ struct aspeed_pwm_tacho_data *priv = data;
+
+ reset_control_assert(priv->rst);
+}
+
static int aspeed_pwm_tacho_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
@@ -931,6 +940,19 @@ 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);
+
+ ret = devm_add_action_or_reset(dev, aspeed_pwm_tacho_remove, priv);
+ if (ret)
+ return ret;
+
regmap_write(priv->regmap, ASPEED_PTCR_TACH_SOURCE, 0);
regmap_write(priv->regmap, ASPEED_PTCR_TACH_SOURCE_EXT, 0);