[PATCH v5 5/9] pwm: rzg2l-gpt: Add info variable to struct rzg2l_gpt_chip

From: Biju

Date: Mon Apr 20 2026 - 06:44:25 EST


From: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>

Introduce struct rzg2l_gpt_info to capture SoC-specific hardware
differences, starting with the gtcr_tpcs field mask for the prescaler
bitfield in GTCR. This is needed because the RZ/G3E GPT has a 4-bit
prescaler field versus the 3-bit field on RZ/G2L.

Reviewed-by: Tommaso Merciai <tommaso.merciai.xr@xxxxxxxxxxxxxx>
Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
---
v4->v5:
* Updated commit description.
v3->v4:
* Dropped field_{get,prep} as mainline now support it.
* Updated commit description.
* Retained RZG2L_GTCR_TPCS bit definitons
* Replaced gtcr_tpcs_mask->gtcr_tpcs
v2->v3:
* No change.
v1->v2:
* Collected tag.
---
drivers/pwm/pwm-rzg2l-gpt.c | 19 +++++++++++++++----
1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/drivers/pwm/pwm-rzg2l-gpt.c b/drivers/pwm/pwm-rzg2l-gpt.c
index 9e7a897a0b4d..af594c1ce536 100644
--- a/drivers/pwm/pwm-rzg2l-gpt.c
+++ b/drivers/pwm/pwm-rzg2l-gpt.c
@@ -90,9 +90,14 @@
#define RZG2L_MAX_POEG_GROUPS 4
#define RZG2L_LAST_POEG_GROUP 3

+struct rzg2l_gpt_info {
+ u32 gtcr_tpcs;
+};
+
struct rzg2l_gpt_chip {
void __iomem *mmio;
struct mutex lock; /* lock to protect shared channel resources */
+ const struct rzg2l_gpt_info *info;
unsigned long rate_khz;
u32 period_ticks[RZG2L_MAX_HW_CHANNELS];
u32 channel_request_count[RZG2L_MAX_HW_CHANNELS];
@@ -346,7 +351,7 @@ static int rzg2l_gpt_read_waveform(struct pwm_chip *chip,

guard(mutex)(&rzg2l_gpt->lock);
if (rzg2l_gpt_is_ch_enabled(rzg2l_gpt, pwm->hwpwm, &gtcr)) {
- wfhw->prescale = FIELD_GET(RZG2L_GTCR_TPCS, gtcr);
+ wfhw->prescale = field_get(rzg2l_gpt->info->gtcr_tpcs, gtcr);
wfhw->gtpr = rzg2l_gpt_read(rzg2l_gpt, RZG2L_GTPR(ch));
wfhw->gtccr = rzg2l_gpt_read(rzg2l_gpt, RZG2L_GTCCR(ch, sub_ch));
if (wfhw->gtccr > wfhw->gtpr)
@@ -386,8 +391,8 @@ static int rzg2l_gpt_write_waveform(struct pwm_chip *chip,
rzg2l_gpt_write(rzg2l_gpt, RZG2L_GTUDDTYC(ch), RZG2L_GTUDDTYC_UP_COUNTING);

/* Select count clock */
- rzg2l_gpt_modify(rzg2l_gpt, RZG2L_GTCR(ch), RZG2L_GTCR_TPCS,
- FIELD_PREP(RZG2L_GTCR_TPCS, wfhw->prescale));
+ rzg2l_gpt_modify(rzg2l_gpt, RZG2L_GTCR(ch), rzg2l_gpt->info->gtcr_tpcs,
+ field_prep(rzg2l_gpt->info->gtcr_tpcs, wfhw->prescale));

/* Set period */
rzg2l_gpt_write(rzg2l_gpt, RZG2L_GTPR(ch), wfhw->gtpr);
@@ -527,6 +532,8 @@ static int rzg2l_gpt_probe(struct platform_device *pdev)
if (IS_ERR(rzg2l_gpt->mmio))
return PTR_ERR(rzg2l_gpt->mmio);

+ rzg2l_gpt->info = of_device_get_match_data(dev);
+
rstc = devm_reset_control_get_exclusive_deasserted(dev, NULL);
if (IS_ERR(rstc))
return dev_err_probe(dev, PTR_ERR(rstc), "Cannot deassert reset control\n");
@@ -573,8 +580,12 @@ static int rzg2l_gpt_probe(struct platform_device *pdev)
return 0;
}

+static const struct rzg2l_gpt_info rzg2l_data = {
+ .gtcr_tpcs = RZG2L_GTCR_TPCS,
+};
+
static const struct of_device_id rzg2l_gpt_of_table[] = {
- { .compatible = "renesas,rzg2l-gpt", },
+ { .compatible = "renesas,rzg2l-gpt", .data = &rzg2l_data },
{ /* Sentinel */ }
};
MODULE_DEVICE_TABLE(of, rzg2l_gpt_of_table);
--
2.43.0