[PATCH] pinctrl: renesas: rzg2l: Add suspend/resume support for pull up/down

[Claudiu <claudiu.beznea@xxxxxxxxx>]

From: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>

The Renesas RZ/G3S supports a power-saving mode where power to most of the
SoC components is lost, including the PIN controller. Save and restore the
pull-up/pull-down register contents to ensure the functionality is
preserved after a suspend/resume cycle.

Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
---
 drivers/pinctrl/renesas/pinctrl-rzg2l.c | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/drivers/pinctrl/renesas/pinctrl-rzg2l.c b/drivers/pinctrl/renesas/pinctrl-rzg2l.c
index 4fae24453c11..7eb91ac5ba42 100644
--- a/drivers/pinctrl/renesas/pinctrl-rzg2l.c
+++ b/drivers/pinctrl/renesas/pinctrl-rzg2l.c
@@ -318,6 +318,7 @@ struct rzg2l_pinctrl_pin_settings {
  * @pmc: PMC registers cache
  * @pfc: PFC registers cache
  * @iolh: IOLH registers cache
+ * @pupd: PUPD registers cache
  * @ien: IEN registers cache
  * @sd_ch: SD_CH registers cache
  * @eth_poc: ET_POC registers cache
@@ -331,6 +332,7 @@ struct rzg2l_pinctrl_reg_cache {
 	u32	*pfc;
 	u32	*iolh[2];
 	u32	*ien[2];
+	u32	*pupd[2];
 	u8	sd_ch[2];
 	u8	eth_poc[2];
 	u8	eth_mode;
@@ -2712,6 +2714,11 @@ static int rzg2l_pinctrl_reg_cache_alloc(struct rzg2l_pinctrl *pctrl)
 		if (!cache->ien[i])
 			return -ENOMEM;
 
+		cache->pupd[i] = devm_kcalloc(pctrl->dev, nports, sizeof(*cache->pupd[i]),
+					      GFP_KERNEL);
+		if (!cache->pupd[i])
+			return -ENOMEM;
+
 		/* Allocate dedicated cache. */
 		dedicated_cache->iolh[i] = devm_kcalloc(pctrl->dev, n_dedicated_pins,
 							sizeof(*dedicated_cache->iolh[i]),
@@ -2953,7 +2960,7 @@ static void rzg2l_pinctrl_pm_setup_regs(struct rzg2l_pinctrl *pctrl, bool suspen
 	struct rzg2l_pinctrl_reg_cache *cache = pctrl->cache;
 
 	for (u32 port = 0; port < nports; port++) {
-		bool has_iolh, has_ien;
+		bool has_iolh, has_ien, has_pupd;
 		u32 off, caps;
 		u8 pincnt;
 		u64 cfg;
@@ -2965,6 +2972,7 @@ static void rzg2l_pinctrl_pm_setup_regs(struct rzg2l_pinctrl *pctrl, bool suspen
 		caps = FIELD_GET(PIN_CFG_MASK, cfg);
 		has_iolh = !!(caps & (PIN_CFG_IOLH_A | PIN_CFG_IOLH_B | PIN_CFG_IOLH_C));
 		has_ien = !!(caps & PIN_CFG_IEN);
+		has_pupd = !!(caps & PIN_CFG_PUPD);
 
 		if (suspend)
 			RZG2L_PCTRL_REG_ACCESS32(suspend, pctrl->base + PFC(off), cache->pfc[port]);
@@ -2983,6 +2991,15 @@ static void rzg2l_pinctrl_pm_setup_regs(struct rzg2l_pinctrl *pctrl, bool suspen
 			}
 		}
 
+		if (has_pupd) {
+			RZG2L_PCTRL_REG_ACCESS32(suspend, pctrl->base + PUPD(off),
+						 cache->pupd[0][port]);
+			if (pincnt >= 4) {
+				RZG2L_PCTRL_REG_ACCESS32(suspend, pctrl->base + PUPD(off),
+							 cache->pupd[1][port]);
+			}
+		}
+
 		RZG2L_PCTRL_REG_ACCESS16(suspend, pctrl->base + PM(off), cache->pm[port]);
 		RZG2L_PCTRL_REG_ACCESS8(suspend, pctrl->base + P(off), cache->p[port]);
 
-- 
2.43.0