[PATCH v5 7/9] pwm: rzg2l-gpt: Add calculate_prescale() callback to struct rzg2l_gpt_info

[Biju]

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

The RZ/G2L GPT prescaler steps are continuous powers of 4, while RZ/G3E
uses powers of 2 but with a discontinuous sequence. Add a
calculate_prescale function pointer to struct rzg2l_gpt_info to allow
per-SoC prescaler selection logic. Replace the direct call to
rzg2l_gpt_calculate_prescale() in rzg2l_gpt_round_waveform_tohw() with an
indirect call through info->calculate_prescale(). Wire the existing
rzg2l_gpt_calculate_prescale() into rzg2l_data to preserve current RZ/G2L
behaviour.

Reviewed-by: Tommaso Merciai <tommaso.merciai.xr@xxxxxxxxxxxxxx>
Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
---
v4->v5:
 * Updated commit description.
v3->v4:
 * No change.
v2->v3:
 * No change.
v1->v2:
 * Collected tag.
---
 drivers/pwm/pwm-rzg2l-gpt.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/pwm/pwm-rzg2l-gpt.c b/drivers/pwm/pwm-rzg2l-gpt.c
index 4324ffc8629d..de68c02b2d50 100644
--- a/drivers/pwm/pwm-rzg2l-gpt.c
+++ b/drivers/pwm/pwm-rzg2l-gpt.c
@@ -91,6 +91,7 @@
 #define RZG2L_LAST_POEG_GROUP	3
 
 struct rzg2l_gpt_info {
+	u8 (*calculate_prescale)(u64 period);
 	u32 gtcr_tpcs;
 	u8 prescale_mult;
 };
@@ -305,7 +306,7 @@ static int rzg2l_gpt_round_waveform_tohw(struct pwm_chip *chip,
 		}
 	}
 
-	wfhw->prescale = rzg2l_gpt_calculate_prescale(rzg2l_gpt, period_ticks);
+	wfhw->prescale = info->calculate_prescale(period_ticks);
 	pv = rzg2l_gpt_calculate_pv_or_dc(info, period_ticks, wfhw->prescale);
 	wfhw->gtpr = pv;
 	wfhw->gtccr = 0;
@@ -587,6 +588,7 @@ static int rzg2l_gpt_probe(struct platform_device *pdev)
 }
 
 static const struct rzg2l_gpt_info rzg2l_data = {
+	.calculate_prescale = rzg2l_gpt_calculate_prescale,
 	.gtcr_tpcs = RZG2L_GTCR_TPCS,
 	.prescale_mult = 2,
 };
-- 
2.43.0