Add code to reset all reset signals as in gpio DT node. A reset property is an optional feature, so only print out a warning and do not fail if a reset property is not present.

If a reset property is discovered, then use it to deassert, thus bringing the IP out of reset.

Signed-off-by: Ley Foon Tan ley.foon.tan@intel.com

--- v4: - Add struct gpio_dwapb_priv

v3: - Add .remove function. - Add error handling when return non-zero from reset_get_bulk().

v2: - Move reset to probe() function. --- drivers/gpio/dwapb_gpio.c | 51 +++++++++++++++++++++++++++++++++++++++++++- 1 files changed, 49 insertions(+), 2 deletions(-)

diff --git a/drivers/gpio/dwapb_gpio.c b/drivers/gpio/dwapb_gpio.c index 7cf2d47..0b88384 100644 --- a/drivers/gpio/dwapb_gpio.c +++ b/drivers/gpio/dwapb_gpio.c @@ -15,6 +15,7 @@ #include <dm/lists.h> #include <dm/root.h> #include <errno.h> +#include <reset.h>

DECLARE_GLOBAL_DATA_PTR;

@@ -29,6 +30,10 @@ DECLARE_GLOBAL_DATA_PTR; #define GPIO_PORTA_EOI 0x4c #define GPIO_EXT_PORT(p) (0x50 + (p) * 4)

+struct gpio_dwapb_priv { + struct reset_ctl_bulk resets; +}; + struct gpio_dwapb_platdata { const char *name; int bank; @@ -99,13 +104,42 @@ static const struct dm_gpio_ops gpio_dwapb_ops = { .get_function = dwapb_gpio_get_function, };

+static int gpio_dwapb_reset(struct udevice *dev) +{ + int ret; + struct gpio_dwapb_priv *priv = dev_get_priv(dev); + + ret = reset_get_bulk(dev, &priv->resets); + if (ret) { + dev_warn(dev, "Can't get reset: %d\n", ret); + /* Return 0 if error due to !CONFIG_DM_RESET and reset + * DT property is not present. + */ + if (ret == -ENOENT || ret == -ENOTSUPP) + return 0; + else + return ret; + } + + ret = reset_deassert_bulk(&priv->resets); + if (ret) { + reset_release_bulk(&priv->resets); + dev_err(dev, "Failed to reset: %d\n", ret); + return ret; + } + + return 0; +} + static int gpio_dwapb_probe(struct udevice *dev) { struct gpio_dev_priv *priv = dev_get_uclass_priv(dev); struct gpio_dwapb_platdata *plat = dev->platdata;

- if (!plat) - return 0; + if (!plat) { + /* Reset on parent device only */ + return gpio_dwapb_reset(dev); + }

priv->gpio_count = plat->pins; priv->bank_name = plat->name; @@ -166,6 +200,17 @@ err: return ret; }

+static int gpio_dwapb_remove(struct udevice *dev) +{ + struct gpio_dwapb_platdata *plat = dev_get_platdata(dev); + struct gpio_dwapb_priv *priv = dev_get_priv(dev); + + if (!plat && priv) + return reset_release_bulk(&priv->resets); + + return 0; +} + static const struct udevice_id gpio_dwapb_ids[] = { { .compatible = "snps,dw-apb-gpio" }, { } @@ -178,4 +223,6 @@ U_BOOT_DRIVER(gpio_dwapb) = { .ops = &gpio_dwapb_ops, .bind = gpio_dwapb_bind, .probe = gpio_dwapb_probe, + .remove = gpio_dwapb_remove, + .priv_auto_alloc_size = sizeof(struct gpio_dwapb_priv), };