From 7c50a407b8687ae3589c740d2347d9ae73887889 Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Wed, 17 Nov 2021 10:59:32 +0100 Subject: [PATCH] pinctrl: renesas: Remove unneeded locking around sh_pfc_read() calls There is no need to acquire the spinlock when reading from a pin controller register: 1. Reading a single MMIO register is an atomic operation, 2. While sh_pfc_phys_to_virt() inside sh_pfc_read() has to traverse all mapped windows to find the appropriate virtual address, this does not need any locking, as the window mappings are never changed. Signed-off-by: Geert Uytterhoeven Link: https://lore.kernel.org/r/2008ca99f0079fd5d4e640b7ef78710c98cc9f77.1637143108.git.geert+renesas@glider.be --- drivers/pinctrl/renesas/pinctrl.c | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-) diff --git a/drivers/pinctrl/renesas/pinctrl.c b/drivers/pinctrl/renesas/pinctrl.c index f3eecb2..96b9de9 100644 --- a/drivers/pinctrl/renesas/pinctrl.c +++ b/drivers/pinctrl/renesas/pinctrl.c @@ -504,7 +504,6 @@ static u32 sh_pfc_pinconf_find_drive_strength_reg(struct sh_pfc *pfc, static int sh_pfc_pinconf_get_drive_strength(struct sh_pfc *pfc, unsigned int pin) { - unsigned long flags; unsigned int offset; unsigned int size; u32 reg; @@ -514,11 +513,7 @@ static int sh_pfc_pinconf_get_drive_strength(struct sh_pfc *pfc, if (!reg) return -EINVAL; - spin_lock_irqsave(&pfc->lock, flags); - val = sh_pfc_read(pfc, reg); - spin_unlock_irqrestore(&pfc->lock, flags); - - val = (val >> offset) & GENMASK(size - 1, 0); + val = (sh_pfc_read(pfc, reg) >> offset) & GENMASK(size - 1, 0); /* Convert the value to mA based on a full drive strength value of 24mA. * We can make the full value configurable later if needed. @@ -648,9 +643,7 @@ static int sh_pfc_pinconf_get(struct pinctrl_dev *pctldev, unsigned _pin, if (WARN(bit < 0, "invalid pin %#x", _pin)) return bit; - spin_lock_irqsave(&pfc->lock, flags); val = sh_pfc_read(pfc, pocctrl); - spin_unlock_irqrestore(&pfc->lock, flags); lower_voltage = (pin->configs & SH_PFC_PIN_VOLTAGE_25_33) ? 2500 : 1800; -- 2.7.4