Re: [PATCH v3 3/3] input: pwm-beeper: add devicetree bindings to set volume levels
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Date: 2017-01-19 21:30:56
Also in:
linux-devicetree, lkml
On Thu, Jan 19, 2017 at 04:24:10PM +0100, Frieder Schrempf wrote:
quoted hunk ↗ jump to hunk
This patch adds the devicetree bindings to set the volume levels and the default volume level. Signed-off-by: Frieder Schrempf <redacted> --- Changes in v3: - none drivers/input/misc/pwm-beeper.c | 49 ++++++++++++++++++++++++++++++++++++++--- 1 file changed, 46 insertions(+), 3 deletions(-)diff --git a/drivers/input/misc/pwm-beeper.c b/drivers/input/misc/pwm-beeper.c index 3ed21da..a7f9d70 100644 --- a/drivers/input/misc/pwm-beeper.c +++ b/drivers/input/misc/pwm-beeper.c@@ -32,7 +32,7 @@ struct pwm_beeper { struct work_struct work; unsigned long period; unsigned int volume; - unsigned int volume_levels[] = {0, 8, 20, 40, 500}; + unsigned int *volume_levels; unsigned int max_volume_level; };@@ -161,8 +161,11 @@ static void pwm_beeper_close(struct input_dev *input) static int pwm_beeper_probe(struct platform_device *pdev) { unsigned long pwm_id = (unsigned long)dev_get_platdata(&pdev->dev); + struct device_node *np = pdev->dev.of_node; struct pwm_beeper *beeper; - int error; + struct property *prop; + int error, length; + u32 value; beeper = kzalloc(sizeof(*beeper), GFP_KERNEL); if (!beeper)@@ -188,7 +191,47 @@ static int pwm_beeper_probe(struct platform_device *pdev) INIT_WORK(&beeper->work, pwm_beeper_work); - beeper->max_volume_level = ARRAY_SIZE(beeper->volume_levels) - 1; + /* determine the number of volume levels */ + prop = of_find_property(np, "volume-levels", &length);
Please use generic device properties, not OF-specific ones.
+ if (!prop) {
+ dev_dbg(&pdev->dev, "no volume levels specified, using max volume\n");
+ beeper->max_volume_level = 1;
+ } else
+ beeper->max_volume_level = length / sizeof(u32);
+
+ /* read volume levels from DT property */
+ if (beeper->max_volume_level > 0) {
+ size_t size = sizeof(*beeper->volume_levels) *
+ beeper->max_volume_level;
+
+ beeper->volume_levels = devm_kzalloc(&(pdev->dev), size,
+ GFP_KERNEL);
+ if (!beeper->volume_levels)
+ return -ENOMEM;
+
+ if (prop) {
+ error = of_property_read_u32_array(np, "volume-levels",
+ beeper->volume_levels,
+ beeper->max_volume_level);
+
+ if (error < 0)
+ return error;
+
+ error = of_property_read_u32(np, "default-volume-level",
+ &value);
+
+ if (error < 0) {
+ dev_dbg(&pdev->dev, "no default volume specified, using max volume\n");
+ value = beeper->max_volume_level - 1;
+ }
+ } else {
+ beeper->volume_levels[0] = 500;
+ value = 0;
+ }
+
+ beeper->volume = value;
+ beeper->max_volume_level--;
+ }
beeper->input = input_allocate_device();
if (!beeper->input) {
--
2.7.4-- Dmitry