drm/tegra: dpaux: Add pinctrl support

The DPAUX pins are shared with an internal I2C controller. To allow
these pins to be muxed to the I2C controller, register a pinctrl device
for the DPAUX device.

This is based upon work by Thierry Reding <treding@nvidia.com>.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
This commit is contained in:
Jon Hunter 2016-06-29 10:17:55 +01:00 committed by Thierry Reding
parent 6cb68e46a9
commit 0751bb5c44

View File

@ -12,6 +12,9 @@
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/of_gpio.h>
#include <linux/pinctrl/pinconf-generic.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/pinctrl/pinmux.h>
#include <linux/platform_device.h>
#include <linux/reset.h>
#include <linux/regulator/consumer.h>
@ -44,6 +47,11 @@ struct tegra_dpaux {
struct completion complete;
struct work_struct work;
struct list_head list;
#ifdef CONFIG_GENERIC_PINCONF
struct pinctrl_dev *pinctrl;
struct pinctrl_desc desc;
#endif
};
static inline struct tegra_dpaux *to_dpaux(struct drm_dp_aux *aux)
@ -267,6 +275,12 @@ static irqreturn_t tegra_dpaux_irq(int irq, void *data)
return ret;
}
enum tegra_dpaux_functions {
DPAUX_PADCTL_FUNC_AUX,
DPAUX_PADCTL_FUNC_I2C,
DPAUX_PADCTL_FUNC_OFF,
};
static void tegra_dpaux_pad_power_down(struct tegra_dpaux *dpaux)
{
u32 value = tegra_dpaux_readl(dpaux, DPAUX_HYBRID_SPARE);
@ -290,7 +304,7 @@ static int tegra_dpaux_pad_config(struct tegra_dpaux *dpaux, unsigned function)
u32 value;
switch (function) {
case DPAUX_HYBRID_PADCTL_MODE_AUX:
case DPAUX_PADCTL_FUNC_AUX:
value = DPAUX_HYBRID_PADCTL_AUX_CMH(2) |
DPAUX_HYBRID_PADCTL_AUX_DRVZ(4) |
DPAUX_HYBRID_PADCTL_AUX_DRVI(0x18) |
@ -298,12 +312,16 @@ static int tegra_dpaux_pad_config(struct tegra_dpaux *dpaux, unsigned function)
DPAUX_HYBRID_PADCTL_MODE_AUX;
break;
case DPAUX_HYBRID_PADCTL_MODE_I2C:
case DPAUX_PADCTL_FUNC_I2C:
value = DPAUX_HYBRID_PADCTL_I2C_SDA_INPUT_RCV |
DPAUX_HYBRID_PADCTL_I2C_SCL_INPUT_RCV |
DPAUX_HYBRID_PADCTL_MODE_I2C;
break;
case DPAUX_PADCTL_FUNC_OFF:
tegra_dpaux_pad_power_down(dpaux);
return 0;
default:
return -ENOTSUPP;
}
@ -314,6 +332,91 @@ static int tegra_dpaux_pad_config(struct tegra_dpaux *dpaux, unsigned function)
return 0;
}
#ifdef CONFIG_GENERIC_PINCONF
static const struct pinctrl_pin_desc tegra_dpaux_pins[] = {
PINCTRL_PIN(0, "DP_AUX_CHx_P"),
PINCTRL_PIN(1, "DP_AUX_CHx_N"),
};
static const unsigned tegra_dpaux_pin_numbers[] = { 0, 1 };
static const char * const tegra_dpaux_groups[] = {
"dpaux-io",
};
static const char * const tegra_dpaux_functions[] = {
"aux",
"i2c",
"off",
};
static int tegra_dpaux_get_groups_count(struct pinctrl_dev *pinctrl)
{
return ARRAY_SIZE(tegra_dpaux_groups);
}
static const char *tegra_dpaux_get_group_name(struct pinctrl_dev *pinctrl,
unsigned int group)
{
return tegra_dpaux_groups[group];
}
static int tegra_dpaux_get_group_pins(struct pinctrl_dev *pinctrl,
unsigned group, const unsigned **pins,
unsigned *num_pins)
{
*pins = tegra_dpaux_pin_numbers;
*num_pins = ARRAY_SIZE(tegra_dpaux_pin_numbers);
return 0;
}
static const struct pinctrl_ops tegra_dpaux_pinctrl_ops = {
.get_groups_count = tegra_dpaux_get_groups_count,
.get_group_name = tegra_dpaux_get_group_name,
.get_group_pins = tegra_dpaux_get_group_pins,
.dt_node_to_map = pinconf_generic_dt_node_to_map_group,
.dt_free_map = pinconf_generic_dt_free_map,
};
static int tegra_dpaux_get_functions_count(struct pinctrl_dev *pinctrl)
{
return ARRAY_SIZE(tegra_dpaux_functions);
}
static const char *tegra_dpaux_get_function_name(struct pinctrl_dev *pinctrl,
unsigned int function)
{
return tegra_dpaux_functions[function];
}
static int tegra_dpaux_get_function_groups(struct pinctrl_dev *pinctrl,
unsigned int function,
const char * const **groups,
unsigned * const num_groups)
{
*num_groups = ARRAY_SIZE(tegra_dpaux_groups);
*groups = tegra_dpaux_groups;
return 0;
}
static int tegra_dpaux_set_mux(struct pinctrl_dev *pinctrl,
unsigned int function, unsigned int group)
{
struct tegra_dpaux *dpaux = pinctrl_dev_get_drvdata(pinctrl);
return tegra_dpaux_pad_config(dpaux, function);
}
static const struct pinmux_ops tegra_dpaux_pinmux_ops = {
.get_functions_count = tegra_dpaux_get_functions_count,
.get_function_name = tegra_dpaux_get_function_name,
.get_function_groups = tegra_dpaux_get_function_groups,
.set_mux = tegra_dpaux_set_mux,
};
#endif
static int tegra_dpaux_probe(struct platform_device *pdev)
{
struct tegra_dpaux *dpaux;
@ -427,6 +530,20 @@ static int tegra_dpaux_probe(struct platform_device *pdev)
if (err < 0)
return err;
#ifdef CONFIG_GENERIC_PINCONF
dpaux->desc.name = dev_name(&pdev->dev);
dpaux->desc.pins = tegra_dpaux_pins;
dpaux->desc.npins = ARRAY_SIZE(tegra_dpaux_pins);
dpaux->desc.pctlops = &tegra_dpaux_pinctrl_ops;
dpaux->desc.pmxops = &tegra_dpaux_pinmux_ops;
dpaux->desc.owner = THIS_MODULE;
dpaux->pinctrl = devm_pinctrl_register(&pdev->dev, &dpaux->desc, dpaux);
if (!dpaux->pinctrl) {
dev_err(&pdev->dev, "failed to register pincontrol\n");
return -ENODEV;
}
#endif
/* enable and clear all interrupts */
value = DPAUX_INTR_AUX_DONE | DPAUX_INTR_IRQ_EVENT |
DPAUX_INTR_UNPLUG_EVENT | DPAUX_INTR_PLUG_EVENT;
@ -586,7 +703,7 @@ int drm_dp_aux_enable(struct drm_dp_aux *aux)
{
struct tegra_dpaux *dpaux = to_dpaux(aux);
return tegra_dpaux_pad_config(dpaux, DPAUX_HYBRID_PADCTL_MODE_AUX);
return tegra_dpaux_pad_config(dpaux, DPAUX_PADCTL_FUNC_AUX);
}
int drm_dp_aux_disable(struct drm_dp_aux *aux)