The Crystalcove PMIC provides three PWM signals and this driver exports
one of them on the BYT platform which is used to control backlight for
DSI panel. This is platform device implementation of the drivers/mfd
cell device for CRC PMIC.
v2: Use the existing config callback with duty_ns and period_ns(Thierry)
v3: Correct the subject line (Lee jones)
v4: Address comment by Thierry & Paul
- Commit message update and fixes for few syntax errors
- Add PWM_CRC in Kconfig and Makefile sorted alphabetically
- Use the PWM_BASE_CLK as 6000000 for better code readability
- Remove the redundant rule of three while calculating pwm level
- Use the platform_device in pwm_chip
- Use builin_platform_driver
CC: Samuel Ortiz <sameo@xxxxxxxxxxxxxxx>
Cc: Linus Walleij <linus.walleij@xxxxxxxxxx>
Cc: Alexandre Courbot <gnurou@xxxxxxxxx>
Cc: Thierry Reding <thierry.reding@xxxxxxxxx>
Cc: Paul Bolle <pebolle@xxxxxxxxxx>
Cc: Paul Gortmaker <paul.gortmaker@xxxxxxxxxxxxx>
Signed-off-by: Shobhit Kumar <shobhit.kumar@xxxxxxxxx>
+
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/mfd/intel_soc_pmic.h>
+#include <linux/pwm.h>
+
+#define PWM0_CLK_DIV 0x4B
+#define PWM_OUTPUT_ENABLE (1 << 7)
+#define PWM_DIV_CLK_0 0x00 /* DIVIDECLK = BASECLK */
+#define PWM_DIV_CLK_100 0x63 /* DIVIDECLK = BASECLK/100 */
+#define PWM_DIV_CLK_128 0x7F /* DIVIDECLK = BASECLK/128 */
+
+#define PWM0_DUTY_CYCLE 0x4E
+#define BACKLIGHT_EN 0x51
+static int crystalcove_pwm_probe(struct platform_device *pdev)
+{
+ struct crystalcove_pwm *pwm;
+ int retval;
+ struct device *dev = pdev->dev.parent;
+ struct intel_soc_pmic *pmic = dev_get_drvdata(dev);
+
+ pwm = devm_kzalloc(&pdev->dev, sizeof(*pwm), GFP_KERNEL);
+ if (!pwm)
+ return -ENOMEM;
+
+ pwm->chip.dev = &pdev->dev;
+ pwm->chip.ops = &crc_pwm_ops;
+ pwm->chip.base = -1;
+ pwm->chip.npwm = 1;
+
+ /* get the PMIC regmap */
+ pwm->regmap = pmic->regmap;
+
+ retval = pwmchip_add(&pwm->chip);
+ if (retval < 0)
+ return retval;
+
+ platform_set_drvdata(pdev, pwm);
+
+ return 0;
+}
+
+static int crystalcove_pwm_remove(struct platform_device *pdev)
+{
+ struct crystalcove_pwm *pwm = platform_get_drvdata(pdev);
+ int retval;
+
+ retval = pwmchip_remove(&pwm->chip);
+ if (retval < 0)
+ return retval;
+
+ dev_dbg(&pdev->dev, "crc-pwm driver removed\n");
+
+ return 0;
+}
+
+static struct platform_driver crystalcove_pwm_driver = {
+ .probe = crystalcove_pwm_probe,
+ .remove = crystalcove_pwm_remove,
+ .driver = {
+ .name = "crystal_cove_pwm",
+ },
+};
+
+builtin_platform_driver(crystalcove_pwm_driver);