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pwm: lp3943: Drop usage of pwm_[gs]et_chip_data() 

Instead of distributing the driver's bookkeeping over 3 (i.e.
LP3943_NUM_PWMS + 1) separately allocated memory chunks, put all together
in struct lp3943_pwm. This reduces the number of memory allocations and
so fragmentation and maybe even the number of cache misses. Also
&lp3943_pwm->pwm_map[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/20230705080650.2353391-5-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>
This commit is contained in:
Uwe Kleine-König 2023-07-05 10:06:46 +02:00 committed by Thierry Reding
parent 89c8de78ce
commit 06cc476775
1 changed files with 7 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
drivers/pwm/pwm-lp3943.c
View File

@ -23,6 +23,7 @@ struct lp3943_pwm {
struct pwm_chip chip;
struct lp3943 *lp3943;
struct lp3943_platform_data *pdata;
struct lp3943_pwm_map pwm_map[LP3943_NUM_PWMS];
};
static inline struct lp3943_pwm *to_lp3943_pwm(struct pwm_chip *chip)
@ -35,13 +36,9 @@ lp3943_pwm_request_map(struct lp3943_pwm *lp3943_pwm, int hwpwm)
{
struct lp3943_platform_data *pdata = lp3943_pwm->pdata;
struct lp3943 *lp3943 = lp3943_pwm->lp3943;
struct lp3943_pwm_map *pwm_map;
struct lp3943_pwm_map *pwm_map = &lp3943_pwm->pwm_map[hwpwm];
int i, offset;
pwm_map = kzalloc(sizeof(*pwm_map), GFP_KERNEL);
if (!pwm_map)
return ERR_PTR(-ENOMEM);
pwm_map->output = pdata->pwms[hwpwm]->output;
pwm_map->num_outputs = pdata->pwms[hwpwm]->num_outputs;
@ -49,10 +46,8 @@ lp3943_pwm_request_map(struct lp3943_pwm *lp3943_pwm, int hwpwm)
offset = pwm_map->output[i];
/* Return an error if the pin is already assigned */
if (test_and_set_bit(offset, &lp3943->pin_used)) {
kfree(pwm_map);
if (test_and_set_bit(offset, &lp3943->pin_used))
return ERR_PTR(-EBUSY);
}
}
return pwm_map;
@ -67,7 +62,7 @@ static int lp3943_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
if (IS_ERR(pwm_map))
return PTR_ERR(pwm_map);
return pwm_set_chip_data(pwm, pwm_map);
return 0;
}
static void lp3943_pwm_free_map(struct lp3943_pwm *lp3943_pwm,
@ -80,14 +75,12 @@ static void lp3943_pwm_free_map(struct lp3943_pwm *lp3943_pwm,
offset = pwm_map->output[i];
clear_bit(offset, &lp3943->pin_used);
}
kfree(pwm_map);
}
static void lp3943_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
{
struct lp3943_pwm *lp3943_pwm = to_lp3943_pwm(chip);
struct lp3943_pwm_map *pwm_map = pwm_get_chip_data(pwm);
struct lp3943_pwm_map *pwm_map = &lp3943_pwm->pwm_map[pwm->hwpwm];
lp3943_pwm_free_map(lp3943_pwm, pwm_map);
}
@ -159,7 +152,7 @@ static int lp3943_pwm_set_mode(struct lp3943_pwm *lp3943_pwm,
static int lp3943_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
{
struct lp3943_pwm *lp3943_pwm = to_lp3943_pwm(chip);
struct lp3943_pwm_map *pwm_map = pwm_get_chip_data(pwm);
struct lp3943_pwm_map *pwm_map = &lp3943_pwm->pwm_map[pwm->hwpwm];
u8 val;
if (pwm->hwpwm == 0)
@ -178,7 +171,7 @@ static int lp3943_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
static void lp3943_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
{
struct lp3943_pwm *lp3943_pwm = to_lp3943_pwm(chip);
struct lp3943_pwm_map *pwm_map = pwm_get_chip_data(pwm);
struct lp3943_pwm_map *pwm_map = &lp3943_pwm->pwm_map[pwm->hwpwm];
/*
* LP3943 outputs are open-drain, so the pin should be configured