Disclaimer: This is just proof of concept, to trigger discussion on this. As pinctrl-single driver is used by many platforms, we should be very careful here. I have kept couple of print statement delibrately to match regmap.
Summary: In some usecases, the external device (in my case it PMIC over I2C) does support pin in multiple configuration, we may need to control/configure them during boot or runtime. In my usecase of PMIC 88PM860, as per spec, 88PM860.GPIO_0 can be configured to 000 = GPIO input mode 001 = GPIO output mode 010 = SLEEPOUTN mirror mode 011 = Buck4 FPWM enable 100 = 32 Khz output buffer mode 101 = PMICINTN output mode 110 = HW_RESET1 mode 111 = HW_RESET2 mode You can get more details on History or past discussion on this subject - https://lkml.org/lkml/2015/6/23/170 So we discussed about using pinctrl-single driver for this, but as we know, pinctrl-single driver has some restrictions, - use raw read/write - use of raw spin lock api's I started with writing fresh driver for pinctrl-i2c, but during that I felt I am just duplicating all the code, so decided to see whether we can reuse pinctrl-single driver. So this patch is proof of concept for using pinctrl-single driver for external devices, over I2C, SPI, etc... The idea here is, Represent external device as another 'pinctrl' device, and get hold of it's regmap using dev_get_regmap() on parent. This works :) Still I haven't figured out how to handle raw_spic_lock api's as I2C bus may sleep and you can not disable preemption. So currently it does print anoying BUG inside pcs_set_mux(). Testing: - I have tested this on BeagleBone Bloack - PXA1928 based platform for MMIO (PXA native muxing) - PMIC 88PM800 muxing (GPIO 0) Comments are welcome...good, bad, accepted, nacked, acked, suggestions... Signed-off-by: Vaibhav Hiremath <vaibhav.hirem...@linaro.org> --- arch/arm64/boot/dts/marvell/pxa1928-helium.dts | 15 +++ drivers/mfd/88pm800.c | 41 +++++++ drivers/pinctrl/pinctrl-single.c | 159 +++++++++++++------------ 3 files changed, 140 insertions(+), 75 deletions(-) diff --git a/arch/arm64/boot/dts/marvell/pxa1928-helium.dts b/arch/arm64/boot/dts/marvell/pxa1928-helium.dts index 91b7a1a..25967a6 100644 --- a/arch/arm64/boot/dts/marvell/pxa1928-helium.dts +++ b/arch/arm64/boot/dts/marvell/pxa1928-helium.dts @@ -138,6 +138,8 @@ status = "okay"; pmic1: 88pm860@30 { compatible = "marvell,88pm800"; + pinctrl-names = "default"; + pinctrl-0 = <&gpio0_32khz_pins>; reg = <0x30>; interrupts = <0 77 0x4>; interrupt-parent = <&gic>; @@ -319,6 +321,19 @@ regulator-max-microvolt = <2800000>; }; }; + pinctrl-i2c { + compatible = "pinctrl-i2c"; + status = "okay"; + + pinctrl-single,size = <0xff>; + pinctrl-single,function-mask = <0xff>; + pinctrl-single,register-width = <8>; + + gpio0_32khz_pins: pinmux_gpio0_32khz_pins { + pinctrl-single,pins = <0x30 0x8>; + }; + + }; rtc { compatible = "marvell,88pm80x-rtc"; status = "okay"; diff --git a/drivers/mfd/88pm800.c b/drivers/mfd/88pm800.c index ae2fbbd..3ca381e 100644 --- a/drivers/mfd/88pm800.c +++ b/drivers/mfd/88pm800.c @@ -128,6 +128,14 @@ static const struct of_device_id pm80x_of_match_table[] = { {}, }; +static struct mfd_cell pinctrl_devs[] = { + { + .name = "pinctrl-i2c", + .of_compatible = "pinctrl-i2c", + .id = -1, + }, +}; + static struct resource rtc_resources[] = { { .name = "88pm80x-rtc", @@ -338,6 +346,21 @@ static int device_onkey_init(struct pm80x_chip *chip, return 0; } +static int device_pinctrl_init(struct pm80x_chip *chip, + struct pm80x_platform_data *pdata) +{ + int ret; + + ret = mfd_add_devices(chip->dev, 0, &pinctrl_devs[0], + ARRAY_SIZE(pinctrl_devs), NULL, 0, NULL); + if (ret) { + dev_err(chip->dev, "Failed to add pinctrl subdev\n"); + return ret; + } + + return 0; +} + static int device_rtc_init(struct pm80x_chip *chip, struct pm80x_platform_data *pdata) { @@ -602,6 +625,12 @@ static int device_800_init(struct pm80x_chip *chip, goto out_dev; } + ret = device_pinctrl_init(chip, pdata); + if (ret) { + dev_err(chip->dev, "Failed to add pinctrl subdev\n"); + goto out; + } + ret = device_rtc_init(chip, pdata); if (ret) { dev_err(chip->dev, "Failed to add rtc subdev\n"); @@ -751,6 +780,8 @@ static int pm800_probe(struct i2c_client *client, struct pm80x_platform_data *pdata = dev_get_platdata(&client->dev); struct device_node *np = client->dev.of_node; struct pm80x_subchip *subchip; + struct pinctrl *p; + struct pinctrl_state *state_default; if (!pdata && !np) { dev_err(&client->dev, @@ -775,6 +806,7 @@ static int pm800_probe(struct i2c_client *client, chip = i2c_get_clientdata(client); + printk("%s:%d chip->regmap - %x\n", __func__, __LINE__, chip->regmap); /* init subchip for PM800 */ subchip = devm_kzalloc(&client->dev, sizeof(struct pm80x_subchip), @@ -811,6 +843,15 @@ static int pm800_probe(struct i2c_client *client, goto err_device_init; } + p = devm_pinctrl_get(&client->dev); + if (p) { + state_default = pinctrl_lookup_state(p, PINCTRL_STATE_DEFAULT); + if (IS_ERR(state_default)) + dev_info(&client->dev, "missing default pinctrl state\n"); + else + pinctrl_select_state(p, state_default); + } + /* System reboot notifier and shutdown callback */ chip->reboot_notifier.notifier_call = reboot_notifier_fn; register_reboot_notifier(&(chip->reboot_notifier)); diff --git a/drivers/pinctrl/pinctrl-single.c b/drivers/pinctrl/pinctrl-single.c index b2de09d..26042df 100644 --- a/drivers/pinctrl/pinctrl-single.c +++ b/drivers/pinctrl/pinctrl-single.c @@ -16,6 +16,7 @@ #include <linux/err.h> #include <linux/list.h> #include <linux/interrupt.h> +#include <linux/regmap.h> #include <linux/irqchip/chained_irq.h> @@ -61,7 +62,7 @@ struct pcs_pingroup { * @val: register value */ struct pcs_func_vals { - void __iomem *reg; + unsigned int reg; unsigned val; unsigned mask; }; @@ -236,6 +237,8 @@ struct pcs_device { unsigned ngroups; unsigned nfuncs; struct pinctrl_desc desc; + struct regmap *regmap; + struct regmap_config regmap_config; unsigned (*read)(void __iomem *reg); void (*write)(unsigned val, void __iomem *reg); }; @@ -263,34 +266,18 @@ static enum pin_config_param pcs_bias[] = { * does not help in this case. */ -static unsigned __maybe_unused pcs_readb(void __iomem *reg) +static unsigned pcs_read(struct regmap *map, unsigned int reg) { - return readb(reg); -} + unsigned int val; -static unsigned __maybe_unused pcs_readw(void __iomem *reg) -{ - return readw(reg); -} - -static unsigned __maybe_unused pcs_readl(void __iomem *reg) -{ - return readl(reg); -} - -static void __maybe_unused pcs_writeb(unsigned val, void __iomem *reg) -{ - writeb(val, reg); -} + regmap_read(map, reg, &val); -static void __maybe_unused pcs_writew(unsigned val, void __iomem *reg) -{ - writew(val, reg); + return val; } -static void __maybe_unused pcs_writel(unsigned val, void __iomem *reg) +static void pcs_write(struct regmap *map, unsigned val, unsigned int reg) { - writel(val, reg); + regmap_write(map, reg, val); } static int pcs_get_groups_count(struct pinctrl_dev *pctldev) @@ -351,7 +338,7 @@ static void pcs_pin_dbg_show(struct pinctrl_dev *pctldev, pcs = pinctrl_dev_get_drvdata(pctldev); mux_bytes = pcs->width / BITS_PER_BYTE; - val = pcs->read(pcs->base + pin * mux_bytes); + val = pcs_read(pcs->regmap, pin * mux_bytes); seq_printf(s, "%08x %s " , val, DRIVER_NAME); } @@ -472,7 +459,7 @@ static int pcs_set_mux(struct pinctrl_dev *pctldev, unsigned fselector, vals = &func->vals[i]; raw_spin_lock_irqsave(&pcs->lock, flags); - val = pcs->read(vals->reg); + val = pcs_read(pcs->regmap, vals->reg); if (pcs->bits_per_mux) mask = vals->mask; @@ -481,7 +468,7 @@ static int pcs_set_mux(struct pinctrl_dev *pctldev, unsigned fselector, val &= ~mask; val |= (vals->val & mask); - pcs->write(val, vals->reg); + pcs_write(pcs->regmap, val, vals->reg); raw_spin_unlock_irqrestore(&pcs->lock, flags); } @@ -507,9 +494,9 @@ static int pcs_request_gpio(struct pinctrl_dev *pctldev, || pin < frange->offset) continue; mux_bytes = pcs->width / BITS_PER_BYTE; - data = pcs->read(pcs->base + pin * mux_bytes) & ~pcs->fmask; + data = pcs_read(pcs->regmap, pin * mux_bytes) & ~pcs->fmask; data |= frange->gpiofunc; - pcs->write(data, pcs->base + pin * mux_bytes); + pcs_write(pcs->regmap, data, pin * mux_bytes); break; } return 0; @@ -579,7 +566,7 @@ static int pcs_pinconf_get(struct pinctrl_dev *pctldev, } offset = pin * (pcs->width / BITS_PER_BYTE); - data = pcs->read(pcs->base + offset) & func->conf[i].mask; + data = pcs_read(pcs->regmap, offset) & func->conf[i].mask; switch (func->conf[i].param) { /* 4 parameters */ case PIN_CONFIG_BIAS_PULL_DOWN: @@ -637,7 +624,7 @@ static int pcs_pinconf_set(struct pinctrl_dev *pctldev, continue; offset = pin * (pcs->width / BITS_PER_BYTE); - data = pcs->read(pcs->base + offset); + data = pcs_read(pcs->regmap, offset); arg = pinconf_to_config_argument(configs[j]); switch (func->conf[i].param) { /* 2 parameters */ @@ -668,7 +655,7 @@ static int pcs_pinconf_set(struct pinctrl_dev *pctldev, default: return -ENOTSUPP; } - pcs->write(data, pcs->base + offset); + pcs_write(pcs->regmap, data, offset); break; } @@ -757,6 +744,7 @@ static int pcs_add_pin(struct pcs_device *pcs, unsigned offset, struct pcs_soc_data *pcs_soc = &pcs->socdata; struct pinctrl_pin_desc *pin; struct pcs_name *pn; + resource_size_t start = 0; int i; i = pcs->pins.cur; @@ -766,22 +754,25 @@ static int pcs_add_pin(struct pcs_device *pcs, unsigned offset, return -ENOMEM; } + if (pcs->res) + start = pcs->res->start; + if (pcs_soc->irq_enable_mask) { unsigned val; - val = pcs->read(pcs->base + offset); + val = pcs_read(pcs->regmap, offset); if (val & pcs_soc->irq_enable_mask) { dev_dbg(pcs->dev, "irq enabled at boot for pin at %lx (%x), clearing\n", - (unsigned long)pcs->res->start + offset, val); + (unsigned long)start + offset, val); val &= ~pcs_soc->irq_enable_mask; - pcs->write(val, pcs->base + offset); + pcs_write(pcs->regmap, val, offset); } } pin = &pcs->pins.pa[i]; pn = &pcs->names[i]; sprintf(pn->name, "%lx.%u", - (unsigned long)pcs->res->start + offset, pin_pos); + (unsigned long)start + offset, pin_pos); pin->name = pn->name; pin->number = i; pcs->pins.cur++; @@ -1168,7 +1159,7 @@ static int pcs_parse_one_pinctrl_entry(struct pcs_device *pcs, offset = be32_to_cpup(mux + index++); val = be32_to_cpup(mux + index++); - vals[found].reg = pcs->base + offset; + vals[found].reg = offset; vals[found].val = val; pin = pcs_get_pin_by_offset(pcs, offset); @@ -1296,7 +1287,7 @@ static int pcs_parse_bits_in_pinctrl_entry(struct pcs_device *pcs, } vals[found].mask = submask; - vals[found].reg = pcs->base + offset; + vals[found].reg = offset; vals[found].val = val_pos; pin = pcs_get_pin_by_offset(pcs, offset); @@ -1540,7 +1531,7 @@ static int pcs_add_gpio_func(struct device_node *node, struct pcs_device *pcs) * @node: list node */ struct pcs_interrupt { - void __iomem *reg; + unsigned int reg; irq_hw_number_t hwirq; unsigned int irq; struct list_head node; @@ -1570,12 +1561,12 @@ static inline void pcs_irq_set(struct pcs_soc_data *pcs_soc, soc_mask = pcs_soc->irq_enable_mask; raw_spin_lock(&pcs->lock); - mask = pcs->read(pcswi->reg); + mask = pcs_read(pcs->regmap, pcswi->reg); if (enable) mask |= soc_mask; else mask &= ~soc_mask; - pcs->write(mask, pcswi->reg); + pcs_write(pcs->regmap, mask, pcswi->reg); raw_spin_unlock(&pcs->lock); } @@ -1644,7 +1635,7 @@ static int pcs_irq_handle(struct pcs_soc_data *pcs_soc) pcswi = list_entry(pos, struct pcs_interrupt, node); raw_spin_lock(&pcs->lock); - mask = pcs->read(pcswi->reg); + mask = pcs_read(pcs->regmap, pcswi->reg); raw_spin_unlock(&pcs->lock); if (mask & pcs_soc->irq_status_mask) { generic_handle_irq(irq_find_mapping(pcs->domain, @@ -1705,7 +1696,7 @@ static int pcs_irqdomain_map(struct irq_domain *d, unsigned int irq, if (!pcswi) return -ENOMEM; - pcswi->reg = pcs->base + hwirq; + pcswi->reg = hwirq; pcswi->hwirq = hwirq; pcswi->irq = irq; @@ -1835,6 +1826,7 @@ static int pcs_probe(struct platform_device *pdev) dev_err(&pdev->dev, "could not allocate\n"); return -ENOMEM; } + pcs->dev = &pdev->dev; raw_spin_lock_init(&pcs->lock); mutex_init(&pcs->mutex); @@ -1868,47 +1860,63 @@ static int pcs_probe(struct platform_device *pdev) pcs->bits_per_mux = of_property_read_bool(np, "pinctrl-single,bit-per-mux"); - res = platform_get_resource(pdev, IORESOURCE_MEM, 0); - if (!res) { - dev_err(pcs->dev, "could not get resource\n"); - return -ENODEV; - } + if (of_device_is_compatible(np, "pinctrl-i2c")) { + pcs->regmap = dev_get_regmap(pdev->dev.parent, NULL); - pcs->res = devm_request_mem_region(pcs->dev, res->start, - resource_size(res), DRIVER_NAME); - if (!pcs->res) { - dev_err(pcs->dev, "could not get mem_region\n"); - return -EBUSY; - } + PCS_GET_PROP_U32("pinctrl-single,size", &pcs->size, + "size not specified\n"); +; + } else { + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(pcs->dev, "could not get resource\n"); + return -ENODEV; + } + + pcs->res = devm_request_mem_region(pcs->dev, res->start, + resource_size(res), DRIVER_NAME); + if (!pcs->res) { + dev_err(pcs->dev, "could not get mem_region\n"); + return -EBUSY; + } + + pcs->size = resource_size(pcs->res); + pcs->base = devm_ioremap(pcs->dev, pcs->res->start, pcs->size); + if (!pcs->base) { + dev_err(pcs->dev, "could not ioremap\n"); + return -ENODEV; + } + + switch (pcs->width) { + case 8: + pcs->regmap_config.reg_bits = 8; + pcs->regmap_config.val_bits = 8; + pcs->regmap_config.reg_stride = 1; + break; + case 16: + pcs->regmap_config.reg_bits = 16; + pcs->regmap_config.val_bits = 16; + pcs->regmap_config.reg_stride = 2; + break; + case 32: + pcs->regmap_config.reg_bits = 32; + pcs->regmap_config.val_bits = 32; + pcs->regmap_config.reg_stride = 4; + break; + default: + break; + } + + pcs->regmap = regmap_init_mmio(&pdev->dev, pcs->base, &pcs->regmap_config); - pcs->size = resource_size(pcs->res); - pcs->base = devm_ioremap(pcs->dev, pcs->res->start, pcs->size); - if (!pcs->base) { - dev_err(pcs->dev, "could not ioremap\n"); - return -ENODEV; } + printk("%s:%d: regmap - %x size - %d\n", __func__ , __LINE__, pcs->regmap, pcs->size); + INIT_RADIX_TREE(&pcs->pgtree, GFP_KERNEL); INIT_RADIX_TREE(&pcs->ftree, GFP_KERNEL); platform_set_drvdata(pdev, pcs); - switch (pcs->width) { - case 8: - pcs->read = pcs_readb; - pcs->write = pcs_writeb; - break; - case 16: - pcs->read = pcs_readw; - pcs->write = pcs_writew; - break; - case 32: - pcs->read = pcs_readl; - pcs->write = pcs_writel; - break; - default: - break; - } - pcs->desc.name = DRIVER_NAME; pcs->desc.pctlops = &pcs_pinctrl_ops; pcs->desc.pmxops = &pcs_pinmux_ops; @@ -2008,6 +2016,7 @@ static const struct of_device_id pcs_of_match[] = { { .compatible = "ti,am437-padconf", .data = &pinctrl_single_am437x }, { .compatible = "pinctrl-single", .data = &pinctrl_single }, { .compatible = "pinconf-single", .data = &pinconf_single }, + { .compatible = "pinctrl-i2c", .data = &pinctrl_single }, { }, }; MODULE_DEVICE_TABLE(of, pcs_of_match); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
