From 3caa7d8c3f03ad6f1b66f10f67dc68cb3af55fe1 Mon Sep 17 00:00:00 2001 From: Laurent Pinchart Date: Wed, 23 Mar 2016 16:06:00 +0200 Subject: [PATCH] pinctrl: sh-pfc: Add drive strength support Add support for the drive-strengh pin configuration using the generic pinconf DT bindings. Signed-off-by: Laurent Pinchart Signed-off-by: Geert Uytterhoeven --- .../bindings/pinctrl/renesas,pfc-pinctrl.txt | 4 +- drivers/pinctrl/sh-pfc/core.c | 15 +++ drivers/pinctrl/sh-pfc/core.h | 3 + drivers/pinctrl/sh-pfc/pinctrl.c | 111 ++++++++++++++++++ drivers/pinctrl/sh-pfc/sh_pfc.h | 17 +++ 5 files changed, 148 insertions(+), 2 deletions(-) diff --git a/Documentation/devicetree/bindings/pinctrl/renesas,pfc-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/renesas,pfc-pinctrl.txt index ffadb7a371f6..74e6ec0339d6 100644 --- a/Documentation/devicetree/bindings/pinctrl/renesas,pfc-pinctrl.txt +++ b/Documentation/devicetree/bindings/pinctrl/renesas,pfc-pinctrl.txt @@ -72,8 +72,8 @@ Pin Configuration Node Properties: The pin configuration parameters use the generic pinconf bindings defined in pinctrl-bindings.txt in this directory. The supported parameters are -bias-disable, bias-pull-up, bias-pull-down and power-source. For pins that -have a configurable I/O voltage, the power-source value should be the +bias-disable, bias-pull-up, bias-pull-down, drive strength and power-source. For +pins that have a configurable I/O voltage, the power-source value should be the nominal I/O voltage in millivolts. diff --git a/drivers/pinctrl/sh-pfc/core.c b/drivers/pinctrl/sh-pfc/core.c index dc3609f0c60b..0497bbb8a8e7 100644 --- a/drivers/pinctrl/sh-pfc/core.c +++ b/drivers/pinctrl/sh-pfc/core.c @@ -175,6 +175,21 @@ void sh_pfc_write_raw_reg(void __iomem *mapped_reg, unsigned int reg_width, BUG(); } +u32 sh_pfc_read_reg(struct sh_pfc *pfc, u32 reg, unsigned int width) +{ + return sh_pfc_read_raw_reg(sh_pfc_phys_to_virt(pfc, reg), width); +} + +void sh_pfc_write_reg(struct sh_pfc *pfc, u32 reg, unsigned int width, u32 data) +{ + if (pfc->info->unlock_reg) + sh_pfc_write_raw_reg( + sh_pfc_phys_to_virt(pfc, pfc->info->unlock_reg), 32, + ~data); + + sh_pfc_write_raw_reg(sh_pfc_phys_to_virt(pfc, reg), width, data); +} + static void sh_pfc_config_reg_helper(struct sh_pfc *pfc, const struct pinmux_cfg_reg *crp, unsigned int in_pos, diff --git a/drivers/pinctrl/sh-pfc/core.h b/drivers/pinctrl/sh-pfc/core.h index 62f53b22ae85..fc05d0c516f3 100644 --- a/drivers/pinctrl/sh-pfc/core.h +++ b/drivers/pinctrl/sh-pfc/core.h @@ -62,6 +62,9 @@ int sh_pfc_unregister_pinctrl(struct sh_pfc *pfc); u32 sh_pfc_read_raw_reg(void __iomem *mapped_reg, unsigned int reg_width); void sh_pfc_write_raw_reg(void __iomem *mapped_reg, unsigned int reg_width, u32 data); +u32 sh_pfc_read_reg(struct sh_pfc *pfc, u32 reg, unsigned int width); +void sh_pfc_write_reg(struct sh_pfc *pfc, u32 reg, unsigned int width, + u32 data); int sh_pfc_get_pin_index(struct sh_pfc *pfc, unsigned int pin); int sh_pfc_config_mux(struct sh_pfc *pfc, unsigned mark, int pinmux_type); diff --git a/drivers/pinctrl/sh-pfc/pinctrl.c b/drivers/pinctrl/sh-pfc/pinctrl.c index 87b0a599afaf..8efaa0631be6 100644 --- a/drivers/pinctrl/sh-pfc/pinctrl.c +++ b/drivers/pinctrl/sh-pfc/pinctrl.c @@ -476,6 +476,91 @@ static const struct pinmux_ops sh_pfc_pinmux_ops = { .gpio_set_direction = sh_pfc_gpio_set_direction, }; +static u32 sh_pfc_pinconf_find_drive_strength_reg(struct sh_pfc *pfc, + unsigned int pin, unsigned int *offset, unsigned int *size) +{ + const struct pinmux_drive_reg_field *field; + const struct pinmux_drive_reg *reg; + unsigned int i; + + for (reg = pfc->info->drive_regs; reg->reg; ++reg) { + for (i = 0; i < ARRAY_SIZE(reg->fields); ++i) { + field = ®->fields[i]; + + if (field->size && field->pin == pin) { + *offset = field->offset; + *size = field->size; + + return reg->reg; + } + } + } + + return 0; +} + +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; + u32 val; + + reg = sh_pfc_pinconf_find_drive_strength_reg(pfc, pin, &offset, &size); + if (!reg) + return -EINVAL; + + spin_lock_irqsave(&pfc->lock, flags); + val = sh_pfc_read_reg(pfc, reg, 32); + spin_unlock_irqrestore(&pfc->lock, flags); + + val = (val >> 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. + */ + return (val + 1) * (size == 2 ? 6 : 3); +} + +static int sh_pfc_pinconf_set_drive_strength(struct sh_pfc *pfc, + unsigned int pin, u16 strength) +{ + unsigned long flags; + unsigned int offset; + unsigned int size; + unsigned int step; + u32 reg; + u32 val; + + reg = sh_pfc_pinconf_find_drive_strength_reg(pfc, pin, &offset, &size); + if (!reg) + return -EINVAL; + + step = size == 2 ? 6 : 3; + + if (strength < step || strength > 24) + return -EINVAL; + + /* Convert the value from mA based on a full drive strength value of + * 24mA. We can make the full value configurable later if needed. + */ + strength = strength / step - 1; + + spin_lock_irqsave(&pfc->lock, flags); + + val = sh_pfc_read_reg(pfc, reg, 32); + val &= ~GENMASK(offset + size - 1, offset); + val |= strength << offset; + + sh_pfc_write_reg(pfc, reg, 32, val); + + spin_unlock_irqrestore(&pfc->lock, flags); + + return 0; +} + /* Check whether the requested parameter is supported for a pin. */ static bool sh_pfc_pinconf_validate(struct sh_pfc *pfc, unsigned int _pin, enum pin_config_param param) @@ -493,6 +578,9 @@ static bool sh_pfc_pinconf_validate(struct sh_pfc *pfc, unsigned int _pin, case PIN_CONFIG_BIAS_PULL_DOWN: return pin->configs & SH_PFC_PIN_CFG_PULL_DOWN; + case PIN_CONFIG_DRIVE_STRENGTH: + return pin->configs & SH_PFC_PIN_CFG_DRIVE_STRENGTH; + case PIN_CONFIG_POWER_SOURCE: return pin->configs & SH_PFC_PIN_CFG_IO_VOLTAGE; @@ -532,6 +620,17 @@ static int sh_pfc_pinconf_get(struct pinctrl_dev *pctldev, unsigned _pin, break; } + case PIN_CONFIG_DRIVE_STRENGTH: { + int ret; + + ret = sh_pfc_pinconf_get_drive_strength(pfc, _pin); + if (ret < 0) + return ret; + + *config = ret; + break; + } + case PIN_CONFIG_POWER_SOURCE: { int ret; @@ -584,6 +683,18 @@ static int sh_pfc_pinconf_set(struct pinctrl_dev *pctldev, unsigned _pin, break; + case PIN_CONFIG_DRIVE_STRENGTH: { + unsigned int arg = + pinconf_to_config_argument(configs[i]); + int ret; + + ret = sh_pfc_pinconf_set_drive_strength(pfc, _pin, arg); + if (ret < 0) + return ret; + + break; + } + case PIN_CONFIG_POWER_SOURCE: { unsigned int arg = pinconf_to_config_argument(configs[i]); diff --git a/drivers/pinctrl/sh-pfc/sh_pfc.h b/drivers/pinctrl/sh-pfc/sh_pfc.h index 87140790d1f1..656ea32f776c 100644 --- a/drivers/pinctrl/sh-pfc/sh_pfc.h +++ b/drivers/pinctrl/sh-pfc/sh_pfc.h @@ -28,6 +28,7 @@ enum { #define SH_PFC_PIN_CFG_PULL_UP (1 << 2) #define SH_PFC_PIN_CFG_PULL_DOWN (1 << 3) #define SH_PFC_PIN_CFG_IO_VOLTAGE (1 << 4) +#define SH_PFC_PIN_CFG_DRIVE_STRENGTH (1 << 5) #define SH_PFC_PIN_CFG_NO_GPIO (1 << 31) struct sh_pfc_pin { @@ -131,6 +132,21 @@ struct pinmux_cfg_reg { { var_fw0, var_fwn, 0 }, \ .enum_ids = (const u16 []) +struct pinmux_drive_reg_field { + u16 pin; + u8 offset; + u8 size; +}; + +struct pinmux_drive_reg { + u32 reg; + const struct pinmux_drive_reg_field fields[8]; +}; + +#define PINMUX_DRIVE_REG(name, r) \ + .reg = r, \ + .fields = + struct pinmux_data_reg { u32 reg; u8 reg_width; @@ -199,6 +215,7 @@ struct sh_pfc_soc_info { #endif const struct pinmux_cfg_reg *cfg_regs; + const struct pinmux_drive_reg *drive_regs; const struct pinmux_data_reg *data_regs; const u16 *pinmux_data; -- 2.20.1