From: Sowjanya Komatineni skomatineni@nvidia.com
[ Upstream commit c2cf351eba2ff6002ce8eb178452219d2521e38e ]
pmx_writel uses writel which inserts write barrier before the register write.
This patch has fix to replace writel with writel_relaxed followed by a readback and memory barrier to ensure write operation is completed for successful pinctrl change.
Acked-by: Thierry Reding treding@nvidia.com Reviewed-by: Dmitry Osipenko digetx@gmail.com Signed-off-by: Sowjanya Komatineni skomatineni@nvidia.com Link: https://lore.kernel.org/r/1565984527-5272-2-git-send-email-skomatineni@nvidi... Signed-off-by: Linus Walleij linus.walleij@linaro.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/pinctrl/tegra/pinctrl-tegra.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/pinctrl/tegra/pinctrl-tegra.c b/drivers/pinctrl/tegra/pinctrl-tegra.c index 186ef98e7b2b8..f1b523beec5b3 100644 --- a/drivers/pinctrl/tegra/pinctrl-tegra.c +++ b/drivers/pinctrl/tegra/pinctrl-tegra.c @@ -32,7 +32,9 @@ static inline u32 pmx_readl(struct tegra_pmx *pmx, u32 bank, u32 reg)
static inline void pmx_writel(struct tegra_pmx *pmx, u32 val, u32 bank, u32 reg) { - writel(val, pmx->regs[bank] + reg); + writel_relaxed(val, pmx->regs[bank] + reg); + /* make sure pinmux register write completed */ + pmx_readl(pmx, bank, reg); }
static int tegra_pinctrl_get_groups_count(struct pinctrl_dev *pctldev)