pwm: renesas: Drop usage of pwm_[gs]et_chip_data()

Instead of distributing the driver's bookkeeping over 5 (i.e.
TPU_CHANNEL_MAX + 1) separately allocated memory chunks, put all together
in struct tpu_device. This reduces the number of memory allocations and
so fragmentation and maybe even the number of cache misses. Also
&tpu->tpd[pwm->hwpwm] is cheaper to evaluate than pwm_get_chip_data(pwm)
as the former is just an addition in machine code while the latter involves
a function call.

Link: https://lore.kernel.org/r/20230705080650.2353391-6-u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

diff --git a/drivers/pwm/pwm-renesas-tpu.c b/drivers/pwm/pwm-renesas-tpu.c
index 1b004e01829a284855d9645e71f6c03abc206204..4239f2c3e8b2a3288bfe43d2a7e7a2cb98a9b2b5 100644 (file)
--- a/drivers/pwm/pwm-renesas-tpu.c
+++ b/drivers/pwm/pwm-renesas-tpu.c
@@ -85,6 +85,7 @@ struct tpu_device {
 
        void __iomem *base;
        struct clk *clk;
+       struct tpu_pwm_device tpd[TPU_CHANNEL_MAX];
 };
 
 #define to_tpu_device(c)       container_of(c, struct tpu_device, chip)
@@ -215,9 +216,7 @@ static int tpu_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
        if (pwm->hwpwm >= TPU_CHANNEL_MAX)
                return -EINVAL;
 
-       tpd = kzalloc(sizeof(*tpd), GFP_KERNEL);
-       if (tpd == NULL)
-               return -ENOMEM;
+       tpd = &tpu->tpd[pwm->hwpwm];
 
        tpd->tpu = tpu;
        tpd->channel = pwm->hwpwm;
@@ -228,24 +227,22 @@ static int tpu_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
 
        tpd->timer_on = false;
 
-       pwm_set_chip_data(pwm, tpd);
-
        return 0;
 }
 
 static void tpu_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
 {
-       struct tpu_pwm_device *tpd = pwm_get_chip_data(pwm);
+       struct tpu_device *tpu = to_tpu_device(chip);
+       struct tpu_pwm_device *tpd = &tpu->tpd[pwm->hwpwm];
 
        tpu_pwm_timer_stop(tpd);
-       kfree(tpd);
 }
 
 static int tpu_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
                          u64 duty_ns, u64 period_ns, bool enabled)
 {
-       struct tpu_pwm_device *tpd = pwm_get_chip_data(pwm);
        struct tpu_device *tpu = to_tpu_device(chip);
+       struct tpu_pwm_device *tpd = &tpu->tpd[pwm->hwpwm];
        unsigned int prescaler;
        bool duty_only = false;
        u32 clk_rate;
@@ -353,7 +350,8 @@ static int tpu_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 static int tpu_pwm_set_polarity(struct pwm_chip *chip, struct pwm_device *pwm,
                                enum pwm_polarity polarity)
 {
-       struct tpu_pwm_device *tpd = pwm_get_chip_data(pwm);
+       struct tpu_device *tpu = to_tpu_device(chip);
+       struct tpu_pwm_device *tpd = &tpu->tpd[pwm->hwpwm];
 
        tpd->polarity = polarity;
 
@@ -362,7 +360,8 @@ static int tpu_pwm_set_polarity(struct pwm_chip *chip, struct pwm_device *pwm,
 
 static int tpu_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
 {
-       struct tpu_pwm_device *tpd = pwm_get_chip_data(pwm);
+       struct tpu_device *tpu = to_tpu_device(chip);
+       struct tpu_pwm_device *tpd = &tpu->tpd[pwm->hwpwm];
        int ret;
 
        ret = tpu_pwm_timer_start(tpd);
@@ -384,7 +383,8 @@ static int tpu_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
 
 static void tpu_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
 {
-       struct tpu_pwm_device *tpd = pwm_get_chip_data(pwm);
+       struct tpu_device *tpu = to_tpu_device(chip);
+       struct tpu_pwm_device *tpd = &tpu->tpd[pwm->hwpwm];
 
        /* The timer must be running to modify the pin output configuration. */
        tpu_pwm_timer_start(tpd);