[PATCH v1 1/7] soc: imx: gpcv2: check for errors when r/w registers

From: Adrien Grassein
Date: Wed Apr 07 2021 - 17:21:56 EST


Errors were not checked after each access to registers
and clocks initialisation.

Signed-off-by: Adrien Grassein <adrien.grassein@xxxxxxxxx>
---
drivers/soc/imx/gpcv2.c | 62 ++++++++++++++++++++++++++++++-----------
1 file changed, 45 insertions(+), 17 deletions(-)

diff --git a/drivers/soc/imx/gpcv2.c b/drivers/soc/imx/gpcv2.c
index db7e7fc321b1..8ec5b1b817c7 100644
--- a/drivers/soc/imx/gpcv2.c
+++ b/drivers/soc/imx/gpcv2.c
@@ -140,8 +140,12 @@ static int imx_gpc_pu_pgc_sw_pxx_req(struct generic_pm_domain *genpd,
int i, ret = 0;
u32 pxx_req;

- regmap_update_bits(domain->regmap, GPC_PGC_CPU_MAPPING,
- domain->bits.map, domain->bits.map);
+ ret = regmap_update_bits(domain->regmap, GPC_PGC_CPU_MAPPING,
+ domain->bits.map, domain->bits.map);
+ if (ret) {
+ dev_err(domain->dev, "failed to map GPC PGC domain\n");
+ return ret;
+ }

if (has_regulator && on) {
ret = regulator_enable(domain->regulator);
@@ -152,19 +156,39 @@ static int imx_gpc_pu_pgc_sw_pxx_req(struct generic_pm_domain *genpd,
}

/* Enable reset clocks for all devices in the domain */
- for (i = 0; i < domain->num_clks; i++)
- clk_prepare_enable(domain->clk[i]);
+ for (i = 0; i < domain->num_clks; i++) {
+ ret = clk_prepare_enable(domain->clk[i]);
+ if (ret) {
+ dev_err(domain->dev, "failed to enable clocks\n");
+ goto disable_clocks;
+ }
+ }

- if (enable_power_control)
- regmap_update_bits(domain->regmap, GPC_PGC_CTRL(domain->pgc),
- GPC_PGC_CTRL_PCR, GPC_PGC_CTRL_PCR);
+ if (enable_power_control) {
+ ret = regmap_update_bits(domain->regmap, GPC_PGC_CTRL(domain->pgc),
+ GPC_PGC_CTRL_PCR, GPC_PGC_CTRL_PCR);
+ if (ret) {
+ dev_err(domain->dev, "failed to enable power control\n");
+ goto disable_clocks;
+ }
+ }

- if (domain->bits.hsk)
- regmap_update_bits(domain->regmap, GPC_PU_PWRHSK,
- domain->bits.hsk, on ? domain->bits.hsk : 0);
+ if (domain->bits.hsk) {
+ ret = regmap_update_bits(domain->regmap, GPC_PU_PWRHSK,
+ domain->bits.hsk,
+ on ? domain->bits.hsk : 0);
+ if (ret) {
+ dev_err(domain->dev, "Failed to initiate handshake\n");
+ goto disable_power_control;
+ }
+ }

- regmap_update_bits(domain->regmap, offset,
- domain->bits.pxx, domain->bits.pxx);
+ ret = regmap_update_bits(domain->regmap, offset,
+ domain->bits.pxx, domain->bits.pxx);
+ if (ret) {
+ dev_err(domain->dev, "failed to command PGC\n");
+ goto disable_power_control;
+ }

/*
* As per "5.5.9.4 Example Code 4" in IMX7DRM.pdf wait
@@ -173,8 +197,15 @@ static int imx_gpc_pu_pgc_sw_pxx_req(struct generic_pm_domain *genpd,
ret = regmap_read_poll_timeout(domain->regmap, offset, pxx_req,
!(pxx_req & domain->bits.pxx),
0, USEC_PER_MSEC);
- if (ret) {
+ if (ret)
dev_err(domain->dev, "failed to command PGC\n");
+
+disable_power_control:
+ if (enable_power_control)
+ regmap_update_bits(domain->regmap, GPC_PGC_CTRL(domain->pgc),
+ GPC_PGC_CTRL_PCR, 0);
+
+ if (ret) {
/*
* If we were in a process of enabling a
* domain and failed we might as well disable
@@ -185,10 +216,7 @@ static int imx_gpc_pu_pgc_sw_pxx_req(struct generic_pm_domain *genpd,
on = !on;
}

- if (enable_power_control)
- regmap_update_bits(domain->regmap, GPC_PGC_CTRL(domain->pgc),
- GPC_PGC_CTRL_PCR, 0);
-
+disable_clocks:
/* Disable reset clocks for all devices in the domain */
for (i = 0; i < domain->num_clks; i++)
clk_disable_unprepare(domain->clk[i]);
--
2.25.1