diff options
author | Linus Walleij <linus.walleij@linaro.org> | 2017-12-02 14:23:09 +0300 |
---|---|---|
committer | Linus Walleij <linus.walleij@linaro.org> | 2017-12-07 11:59:26 +0300 |
commit | ad63da85f45fa55c270e5681e9b985605ec51f8d (patch) | |
tree | 004fb4c10fa490e08713dde7118cff5ed45e24b8 /drivers | |
parent | 3881c4a56e5941c21c08d9476c68d2cc65005f68 (diff) | |
download | linux-ad63da85f45fa55c270e5681e9b985605ec51f8d.tar.xz |
pinctrl: gemini: Support drive strength setting
The Gemini pin controller can set drive strength for a few
select groups of pins (not individually). Implement this
for GMAC0 and 1 (ethernet ports), IDE and PCI.
Cc: devicetree@vger.kernel.org
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/pinctrl/pinctrl-gemini.c | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/drivers/pinctrl/pinctrl-gemini.c b/drivers/pinctrl/pinctrl-gemini.c index 10f8f3a35fe1..5e789753f945 100644 --- a/drivers/pinctrl/pinctrl-gemini.c +++ b/drivers/pinctrl/pinctrl-gemini.c @@ -67,6 +67,9 @@ struct gemini_pmx { * elements in .pins so we can iterate over that array * @mask: bits to clear to enable this when doing pin muxing * @value: bits to set to enable this when doing pin muxing + * @driving_mask: bitmask for the IO Pad driving register for this + * group, if it supports altering the driving strength of + * its lines. */ struct gemini_pin_group { const char *name; @@ -74,12 +77,14 @@ struct gemini_pin_group { const unsigned int num_pins; u32 mask; u32 value; + u32 driving_mask; }; /* Some straight-forward control registers */ #define GLOBAL_WORD_ID 0x00 #define GLOBAL_STATUS 0x04 #define GLOBAL_STATUS_FLPIN BIT(20) +#define GLOBAL_IODRIVE 0x10 #define GLOBAL_GMAC_CTRL_SKEW 0x1c #define GLOBAL_GMAC0_DATA_SKEW 0x20 #define GLOBAL_GMAC1_DATA_SKEW 0x24 @@ -738,6 +743,7 @@ static const struct gemini_pin_group gemini_3512_pin_groups[] = { /* Conflict with all flash usage */ .value = IDE_PADS_ENABLE | NAND_PADS_DISABLE | PFLASH_PADS_DISABLE | SFLASH_PADS_DISABLE, + .driving_mask = GENMASK(21, 20), }, { .name = "satagrp", @@ -753,6 +759,7 @@ static const struct gemini_pin_group gemini_3512_pin_groups[] = { .name = "gmii_gmac0_grp", .pins = gmii_gmac0_3512_pins, .num_pins = ARRAY_SIZE(gmii_gmac0_3512_pins), + .driving_mask = GENMASK(17, 16), }, { .name = "gmii_gmac1_grp", @@ -760,6 +767,7 @@ static const struct gemini_pin_group gemini_3512_pin_groups[] = { .num_pins = ARRAY_SIZE(gmii_gmac1_3512_pins), /* Bring out RGMII on the GMAC1 pins */ .value = GEMINI_GMAC_IOSEL_GMAC0_GMAC1_RGMII, + .driving_mask = GENMASK(19, 18), }, { .name = "pcigrp", @@ -767,6 +775,7 @@ static const struct gemini_pin_group gemini_3512_pin_groups[] = { .num_pins = ARRAY_SIZE(pci_3512_pins), /* Conflict only with GPIO2 */ .value = PCI_PADS_ENABLE | PCI_CLK_PAD_ENABLE, + .driving_mask = GENMASK(23, 22), }, { .name = "lpcgrp", @@ -1671,6 +1680,7 @@ static const struct gemini_pin_group gemini_3516_pin_groups[] = { /* Conflict with all flash usage */ .value = IDE_PADS_ENABLE | NAND_PADS_DISABLE | PFLASH_PADS_DISABLE | SFLASH_PADS_DISABLE, + .driving_mask = GENMASK(21, 20), }, { .name = "satagrp", @@ -1686,6 +1696,7 @@ static const struct gemini_pin_group gemini_3516_pin_groups[] = { .name = "gmii_gmac0_grp", .pins = gmii_gmac0_3516_pins, .num_pins = ARRAY_SIZE(gmii_gmac0_3516_pins), + .driving_mask = GENMASK(17, 16), }, { .name = "gmii_gmac1_grp", @@ -1693,6 +1704,7 @@ static const struct gemini_pin_group gemini_3516_pin_groups[] = { .num_pins = ARRAY_SIZE(gmii_gmac1_3516_pins), /* Bring out RGMII on the GMAC1 pins */ .value = GEMINI_GMAC_IOSEL_GMAC0_GMAC1_RGMII, + .driving_mask = GENMASK(19, 18), }, { .name = "pcigrp", @@ -1700,6 +1712,7 @@ static const struct gemini_pin_group gemini_3516_pin_groups[] = { .num_pins = ARRAY_SIZE(pci_3516_pins), /* Conflict only with GPIO2 */ .value = PCI_PADS_ENABLE | PCI_CLK_PAD_ENABLE, + .driving_mask = GENMASK(23, 22), }, { .name = "lpcgrp", @@ -2394,9 +2407,77 @@ static int gemini_pinconf_set(struct pinctrl_dev *pctldev, unsigned int pin, return ret; } +static int gemini_pinconf_group_set(struct pinctrl_dev *pctldev, + unsigned selector, + unsigned long *configs, + unsigned num_configs) +{ + struct gemini_pmx *pmx = pinctrl_dev_get_drvdata(pctldev); + const struct gemini_pin_group *grp = NULL; + enum pin_config_param param; + u32 arg; + u32 val; + int i; + + if (pmx->is_3512) + grp = &gemini_3512_pin_groups[selector]; + if (pmx->is_3516) + grp = &gemini_3516_pin_groups[selector]; + + /* First figure out if this group supports configs */ + if (!grp->driving_mask) { + dev_err(pmx->dev, "pin config group \"%s\" does " + "not support drive strength setting\n", + grp->name); + return -EINVAL; + } + + for (i = 0; i < num_configs; i++) { + param = pinconf_to_config_param(configs[i]); + arg = pinconf_to_config_argument(configs[i]); + + switch (param) { + case PIN_CONFIG_DRIVE_STRENGTH: + switch (arg) { + case 4: + val = 0; + break; + case 8: + val = 1; + break; + case 12: + val = 2; + break; + case 16: + val = 3; + break; + default: + dev_err(pmx->dev, + "invalid drive strength %d mA\n", + arg); + return -ENOTSUPP; + } + val <<= (ffs(grp->driving_mask) - 1); + regmap_update_bits(pmx->map, GLOBAL_IODRIVE, + grp->driving_mask, + val); + dev_info(pmx->dev, + "set group %s to %d mA drive strength mask %08x val %08x\n", + grp->name, arg, grp->driving_mask, val); + break; + default: + dev_err(pmx->dev, "invalid config param %04x\n", param); + return -ENOTSUPP; + } + } + + return 0; +} + static const struct pinconf_ops gemini_pinconf_ops = { .pin_config_get = gemini_pinconf_get, .pin_config_set = gemini_pinconf_set, + .pin_config_group_set = gemini_pinconf_group_set, .is_generic = true, }; |