5.4-stable review patch. If anyone has any objections, please let me know.
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From: Uwe Kleine-König u.kleine-koenig@pengutronix.de
[ Upstream commit 2d6812b41e0d832919d72c72ebddf361df53ba1b ]
Instead of using one allocation per capture channel, use a single one. Also store it in driver data instead of chip data.
This has several advantages:
- driver data isn't cleared when pwm_put() is called - Reduces memory fragmentation
Also register the pwm chip only after the per capture channel data is initialized as the capture callback relies on this initialization and it might be called even before pwmchip_add() returns.
It would be still better to have struct sti_pwm_compat_data and the per-channel data struct sti_cpt_ddata in a single memory chunk, but that's not easily possible because the number of capture channels isn't known yet when the driver data struct is allocated.
Fixes: e926b12c611c ("pwm: Clear chip_data in pwm_put()") Reported-by: George Stark gnstark@sberdevices.ru Fixes: c97267ae831d ("pwm: sti: Add PWM capture callback") Link: https://lore.kernel.org/r/20230705080650.2353391-7-u.kleine-koenig@pengutron... Signed-off-by: Uwe Kleine-König u.kleine-koenig@pengutronix.de Signed-off-by: Thierry Reding thierry.reding@gmail.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/pwm/pwm-sti.c | 29 ++++++++++++++--------------- 1 file changed, 14 insertions(+), 15 deletions(-)
diff --git a/drivers/pwm/pwm-sti.c b/drivers/pwm/pwm-sti.c index 973f76856a508..9b2174adab3db 100644 --- a/drivers/pwm/pwm-sti.c +++ b/drivers/pwm/pwm-sti.c @@ -79,6 +79,7 @@ struct sti_pwm_compat_data { unsigned int cpt_num_devs; unsigned int max_pwm_cnt; unsigned int max_prescale; + struct sti_cpt_ddata *ddata; };
struct sti_pwm_chip { @@ -314,7 +315,7 @@ static int sti_pwm_capture(struct pwm_chip *chip, struct pwm_device *pwm, { struct sti_pwm_chip *pc = to_sti_pwmchip(chip); struct sti_pwm_compat_data *cdata = pc->cdata; - struct sti_cpt_ddata *ddata = pwm_get_chip_data(pwm); + struct sti_cpt_ddata *ddata = &cdata->ddata[pwm->hwpwm]; struct device *dev = pc->dev; unsigned int effective_ticks; unsigned long long high, low; @@ -417,7 +418,7 @@ static irqreturn_t sti_pwm_interrupt(int irq, void *data) while (cpt_int_stat) { devicenum = ffs(cpt_int_stat) - 1;
- ddata = pwm_get_chip_data(&pc->chip.pwms[devicenum]); + ddata = &pc->cdata->ddata[devicenum];
/* * Capture input: @@ -619,6 +620,10 @@ static int sti_pwm_probe(struct platform_device *pdev) dev_err(dev, "failed to prepare clock\n"); return ret; } + + cdata->ddata = devm_kzalloc(dev, cdata->cpt_num_devs * sizeof(*cdata->ddata), GFP_KERNEL); + if (!cdata->ddata) + return -ENOMEM; }
pc->chip.dev = dev; @@ -626,24 +631,18 @@ static int sti_pwm_probe(struct platform_device *pdev) pc->chip.base = -1; pc->chip.npwm = pc->cdata->pwm_num_devs;
- ret = pwmchip_add(&pc->chip); - if (ret < 0) { - clk_unprepare(pc->pwm_clk); - clk_unprepare(pc->cpt_clk); - return ret; - } - for (i = 0; i < cdata->cpt_num_devs; i++) { - struct sti_cpt_ddata *ddata; - - ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL); - if (!ddata) - return -ENOMEM; + struct sti_cpt_ddata *ddata = &cdata->ddata[i];
init_waitqueue_head(&ddata->wait); mutex_init(&ddata->lock); + }
- pwm_set_chip_data(&pc->chip.pwms[i], ddata); + ret = pwmchip_add(&pc->chip); + if (ret < 0) { + clk_unprepare(pc->pwm_clk); + clk_unprepare(pc->cpt_clk); + return ret; }
platform_set_drvdata(pdev, pc);