Property to set initial value of pin output buffer.
Signed-off-by: Matheus Castello <math...@castello.eng.br>
---
.../bindings/pinctrl/brcm,bcm2835-gpio.txt | 5 +-
drivers/pinctrl/bcm/pinctrl-bcm2835.c | 90 +++++++++++++++++-----
2 files changed, 75 insertions(+), 20 deletions(-)
diff --git a/Documentation/devicetree/bindings/pinctrl/brcm,bcm2835-gpio.txt
b/Documentation/devicetree/bindings/pinctrl/brcm,bcm2835-gpio.txt
index 2569866..6834f1d 100644
--- a/Documentation/devicetree/bindings/pinctrl/brcm,bcm2835-gpio.txt
+++ b/Documentation/devicetree/bindings/pinctrl/brcm,bcm2835-gpio.txt
@@ -54,8 +54,11 @@ Optional subnode-properties:
0: none
1: down
2: up
+- brcm,level: Integer, representing the value of output buffer to apply to the
pin(s):
+ 0: low
+ 1: high
-Each of brcm,function and brcm,pull may contain either a single value which
+Each of brcm,function, brcm,pull and brcm,level may contain either a single
value which
will be applied to all pins in brcm,pins, or 1 value for each entry in
brcm,pins.
diff --git a/drivers/pinctrl/bcm/pinctrl-bcm2835.c
b/drivers/pinctrl/bcm/pinctrl-bcm2835.c
index 785c366..0ace548 100644
--- a/drivers/pinctrl/bcm/pinctrl-bcm2835.c
+++ b/drivers/pinctrl/bcm/pinctrl-bcm2835.c
@@ -73,6 +73,8 @@
enum bcm2835_pinconf_param {
/* argument: bcm2835_pinconf_pull */
BCM2835_PINCONF_PARAM_PULL,
+ /* argument: bcm2835_pinconf_level */
+ BCM2835_PINCONF_PARAM_LEVEL,
};
#define BCM2835_PINCONF_PACK(_param_, _arg_) ((_param_) << 16 | (_arg_))
@@ -725,16 +727,42 @@ static int bcm2835_pctl_dt_node_to_map_pull(struct
bcm2835_pinctrl *pc,
return 0;
}
+static int bcm2835_pctl_dt_node_to_map_level(struct bcm2835_pinctrl *pc,
+ struct device_node *np, u32 pin, u32 level,
+ struct pinctrl_map **maps)
+{
+ struct pinctrl_map *map = *maps;
+ unsigned long *configs;
+
+ if (level > 2) {
+ dev_err(pc->dev, "%pOF: invalid brcm,level %d\n", np, level);
+ return -EINVAL;
+ }
+
+ configs = kzalloc(sizeof(*configs), GFP_KERNEL);
+ if (!configs)
+ return -ENOMEM;
+ configs[0] = BCM2835_PINCONF_PACK(BCM2835_PINCONF_PARAM_LEVEL, level);
+
+ map->type = PIN_MAP_TYPE_CONFIGS_PIN;
+ map->data.configs.group_or_pin = bcm2835_gpio_pins[pin].name;
+ map->data.configs.configs = configs;
+ map->data.configs.num_configs = 1;
+ (*maps)++;
+
+ return 0;
+}
+
static int bcm2835_pctl_dt_node_to_map(struct pinctrl_dev *pctldev,
struct device_node *np,
struct pinctrl_map **map, unsigned *num_maps)
{
struct bcm2835_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev);
- struct property *pins, *funcs, *pulls;
- int num_pins, num_funcs, num_pulls, maps_per_pin;
+ struct property *pins, *funcs, *pulls, *levels;
+ int num_pins, num_funcs, num_pulls, num_levels, maps_per_pin;
struct pinctrl_map *maps, *cur_map;
int i, err;
- u32 pin, func, pull;
+ u32 pin, func, pull, level;
pins = of_find_property(np, "brcm,pins", NULL);
if (!pins) {
@@ -744,6 +772,7 @@ static int bcm2835_pctl_dt_node_to_map(struct pinctrl_dev
*pctldev,
funcs = of_find_property(np, "brcm,function", NULL);
pulls = of_find_property(np, "brcm,pull", NULL);
+ levels = of_find_property(np, "brcm,level", NULL);
if (!funcs && !pulls) {
dev_err(pc->dev,
@@ -755,6 +784,7 @@ static int bcm2835_pctl_dt_node_to_map(struct pinctrl_dev
*pctldev,
num_pins = pins->length / 4;
num_funcs = funcs ? (funcs->length / 4) : 0;
num_pulls = pulls ? (pulls->length / 4) : 0;
+ num_levels = levels ? (levels->length / 4) : 0;
if (num_funcs > 1 && num_funcs != num_pins) {
dev_err(pc->dev,
@@ -770,11 +800,20 @@ static int bcm2835_pctl_dt_node_to_map(struct pinctrl_dev
*pctldev,
return -EINVAL;
}
+ if (num_levels > 1 && num_levels != num_pins) {
+ dev_err(pc->dev,
+ "%pOF: brcm,level must have 1 or %d entries\n",
+ np, num_pins);
+ return -EINVAL;
+ }
+
maps_per_pin = 0;
if (num_funcs)
maps_per_pin++;
if (num_pulls)
maps_per_pin++;
+ if (num_levels)
+ maps_per_pin++;
cur_map = maps = kzalloc(num_pins * maps_per_pin * sizeof(*maps),
GFP_KERNEL);
if (!maps)
@@ -811,6 +850,17 @@ static int bcm2835_pctl_dt_node_to_map(struct pinctrl_dev
*pctldev,
if (err)
goto out;
}
+ if (num_levels) {
+ err = of_property_read_u32_index(np, "brcm,level",
+ (num_levels > 1) ? i : 0, &level);
+ if (err)
+ goto out;
+
+ err = bcm2835_pctl_dt_node_to_map_level(pc, np, pin,
+ level, &cur_map);
+ if (err)
+ goto out;
+ }
}
*map = maps;
@@ -931,23 +981,25 @@ static int bcm2835_pinconf_set(struct pinctrl_dev
*pctldev,
param = BCM2835_PINCONF_UNPACK_PARAM(configs[i]);
arg = BCM2835_PINCONF_UNPACK_ARG(configs[i]);
- if (param != BCM2835_PINCONF_PARAM_PULL)
+ if (param == BCM2835_PINCONF_PARAM_PULL) {
+ off = GPIO_REG_OFFSET(pin);
+ bit = GPIO_REG_SHIFT(pin);
+
+ bcm2835_gpio_wr(pc, GPPUD, arg & 3);
+ /*
+ * Docs say to wait 150 cycles, but not of what. We
assume a
+ * 1 MHz clock here, which is pretty slow...
+ */
+ udelay(150);
+ bcm2835_gpio_wr(pc, GPPUDCLK0 + (off * 4), BIT(bit));
+ udelay(150);
+ bcm2835_gpio_wr(pc, GPPUDCLK0 + (off * 4), 0);
+ } else if (param == BCM2835_PINCONF_PARAM_LEVEL) {
+ /* write in register */
+ bcm2835_gpio_set_bit(pc, arg ? GPSET0 : GPCLR0, pin);
+ } else {
return -EINVAL;
-
- off = GPIO_REG_OFFSET(pin);
- bit = GPIO_REG_SHIFT(pin);
-
- bcm2835_gpio_wr(pc, GPPUD, arg & 3);
- /*
- * BCM2835 datasheet say to wait 150 cycles, but not of what.
- * But the VideoCore firmware delay for this operation
- * based nearly on the same amount of VPU cycles and this clock
- * runs at 250 MHz.
- */
- udelay(1);
- bcm2835_gpio_wr(pc, GPPUDCLK0 + (off * 4), BIT(bit));
- udelay(1);
- bcm2835_gpio_wr(pc, GPPUDCLK0 + (off * 4), 0);
+ }
} /* for each config */
return 0;
--
2.7.4
