pwm: meson: Add the meson_pwm_channel data to struct meson_pwm

Make struct meson_pwm_channel accessible from struct meson_pwm.

PWM core has a limitation: per-channel data can only be set after
pwmchip_add() is called. However, pwmchip_add() internally calls
pwm_ops.get_state(). If pwm_ops.get_state() needs access to the
per-channel data it has to obtain it from struct pwm_chip and struct
pwm_device's hwpwm information.

Add a struct meson_pwm_channel for each PWM channel to struct meson_pwm
so the pwm_ops.get_state() callback can be implemented as it needs
access to the clock from struct meson_pwm_channel.

Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c
index 6e44fc8..207e594 100644 (file)
--- a/drivers/pwm/pwm-meson.c
+++ b/drivers/pwm/pwm-meson.c
@@ -37,6 +37,8 @@
 #define MISC_B_EN              BIT(1)
 #define MISC_A_EN              BIT(0)
 
+#define MESON_NUM_PWMS         2
+
 static const unsigned int mux_reg_shifts[] = {
        MISC_A_CLK_SEL_SHIFT,
        MISC_B_CLK_SEL_SHIFT
@@ -62,6 +64,7 @@ struct meson_pwm_data {
 struct meson_pwm {
        struct pwm_chip chip;
        const struct meson_pwm_data *data;
+       struct meson_pwm_channel channels[MESON_NUM_PWMS];
        void __iomem *base;
        /*
         * Protects register (write) access to the REG_MISC_AB register
@@ -444,8 +447,7 @@ static const struct of_device_id meson_pwm_matches[] = {
 };
 MODULE_DEVICE_TABLE(of, meson_pwm_matches);
 
-static int meson_pwm_init_channels(struct meson_pwm *meson,
-                                  struct meson_pwm_channel *channels)
+static int meson_pwm_init_channels(struct meson_pwm *meson)
 {
        struct device *dev = meson->chip.dev;
        struct clk_init_data init;
@@ -454,7 +456,7 @@ static int meson_pwm_init_channels(struct meson_pwm *meson,
        int err;
 
        for (i = 0; i < meson->chip.npwm; i++) {
-               struct meson_pwm_channel *channel = &channels[i];
+               struct meson_pwm_channel *channel = &meson->channels[i];
 
                snprintf(name, sizeof(name), "%s#mux%u", dev_name(dev), i);
 
@@ -489,18 +491,16 @@ static int meson_pwm_init_channels(struct meson_pwm *meson,
        return 0;
 }
 
-static void meson_pwm_add_channels(struct meson_pwm *meson,
-                                  struct meson_pwm_channel *channels)
+static void meson_pwm_add_channels(struct meson_pwm *meson)
 {
        unsigned int i;
 
        for (i = 0; i < meson->chip.npwm; i++)
-               pwm_set_chip_data(&meson->chip.pwms[i], &channels[i]);
+               pwm_set_chip_data(&meson->chip.pwms[i], &meson->channels[i]);
 }
 
 static int meson_pwm_probe(struct platform_device *pdev)
 {
-       struct meson_pwm_channel *channels;
        struct meson_pwm *meson;
        struct resource *regs;
        int err;
@@ -518,18 +518,13 @@ static int meson_pwm_probe(struct platform_device *pdev)
        meson->chip.dev = &pdev->dev;
        meson->chip.ops = &meson_pwm_ops;
        meson->chip.base = -1;
-       meson->chip.npwm = 2;
+       meson->chip.npwm = MESON_NUM_PWMS;
        meson->chip.of_xlate = of_pwm_xlate_with_flags;
        meson->chip.of_pwm_n_cells = 3;
 
        meson->data = of_device_get_match_data(&pdev->dev);
 
-       channels = devm_kcalloc(&pdev->dev, meson->chip.npwm,
-                               sizeof(*channels), GFP_KERNEL);
-       if (!channels)
-               return -ENOMEM;
-
-       err = meson_pwm_init_channels(meson, channels);
+       err = meson_pwm_init_channels(meson);
        if (err < 0)
                return err;
 
@@ -539,7 +534,7 @@ static int meson_pwm_probe(struct platform_device *pdev)
                return err;
        }
 
-       meson_pwm_add_channels(meson, channels);
+       meson_pwm_add_channels(meson);
 
        platform_set_drvdata(pdev, meson);