[PATCH v1 2/2] drm/i915/dsi: Replace poking of VLV GPIOs behind the driver's back

From: Andy Shevchenko
Date: Wed Oct 18 2023 - 01:11:18 EST


It's a dirty hack in the driver that pokes GPIO registers behind
the driver's back. Moreoever it might be problematic as simultaneous
I/O may hang the system, see the commit 40ecab551232 ("pinctrl:
baytrail: Really serialize all register accesses") for the details.
Taking all this into consideration replace the hack with proper
GPIO APIs being used.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
drivers/gpu/drm/i915/display/intel_dsi_vbt.c | 101 ++++++-------------
1 file changed, 31 insertions(+), 70 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_dsi_vbt.c b/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
index c3c3f4df9ac4..35ab4048029d 100644
--- a/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
+++ b/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
@@ -55,43 +55,6 @@
#define MIPI_VIRTUAL_CHANNEL_SHIFT 1
#define MIPI_PORT_SHIFT 3

-/* base offsets for gpio pads */
-#define VLV_GPIO_NC_0_HV_DDI0_HPD 0x4130
-#define VLV_GPIO_NC_1_HV_DDI0_DDC_SDA 0x4120
-#define VLV_GPIO_NC_2_HV_DDI0_DDC_SCL 0x4110
-#define VLV_GPIO_NC_3_PANEL0_VDDEN 0x4140
-#define VLV_GPIO_NC_4_PANEL0_BKLTEN 0x4150
-#define VLV_GPIO_NC_5_PANEL0_BKLTCTL 0x4160
-#define VLV_GPIO_NC_6_HV_DDI1_HPD 0x4180
-#define VLV_GPIO_NC_7_HV_DDI1_DDC_SDA 0x4190
-#define VLV_GPIO_NC_8_HV_DDI1_DDC_SCL 0x4170
-#define VLV_GPIO_NC_9_PANEL1_VDDEN 0x4100
-#define VLV_GPIO_NC_10_PANEL1_BKLTEN 0x40E0
-#define VLV_GPIO_NC_11_PANEL1_BKLTCTL 0x40F0
-
-#define VLV_GPIO_PCONF0(base_offset) (base_offset)
-#define VLV_GPIO_PAD_VAL(base_offset) ((base_offset) + 8)
-
-struct gpio_map {
- u16 base_offset;
- bool init;
-};
-
-static struct gpio_map vlv_gpio_table[] = {
- { VLV_GPIO_NC_0_HV_DDI0_HPD },
- { VLV_GPIO_NC_1_HV_DDI0_DDC_SDA },
- { VLV_GPIO_NC_2_HV_DDI0_DDC_SCL },
- { VLV_GPIO_NC_3_PANEL0_VDDEN },
- { VLV_GPIO_NC_4_PANEL0_BKLTEN },
- { VLV_GPIO_NC_5_PANEL0_BKLTCTL },
- { VLV_GPIO_NC_6_HV_DDI1_HPD },
- { VLV_GPIO_NC_7_HV_DDI1_DDC_SDA },
- { VLV_GPIO_NC_8_HV_DDI1_DDC_SCL },
- { VLV_GPIO_NC_9_PANEL1_VDDEN },
- { VLV_GPIO_NC_10_PANEL1_BKLTEN },
- { VLV_GPIO_NC_11_PANEL1_BKLTCTL },
-};
-
struct i2c_adapter_lookup {
u16 slave_addr;
struct intel_dsi *intel_dsi;
@@ -269,52 +232,44 @@ static void soc_exec_gpio(struct intel_connector *connector, const char *con_id,
}
}

+static struct gpiod_lookup_table vlv_gpio_table = {
+ .dev_id = "0000:00:02.0",
+ .table = {
+ GPIO_LOOKUP_IDX("INT33FC:01", 0, "Panel NC", 0, GPIO_ACTIVE_HIGH),
+ GPIO_LOOKUP_IDX("INT33FC:01", 1, "Panel NC", 1, GPIO_ACTIVE_HIGH),
+ GPIO_LOOKUP_IDX("INT33FC:01", 2, "Panel NC", 2, GPIO_ACTIVE_HIGH),
+ GPIO_LOOKUP_IDX("INT33FC:01", 3, "Panel NC", 3, GPIO_ACTIVE_HIGH),
+ GPIO_LOOKUP_IDX("INT33FC:01", 4, "Panel NC", 4, GPIO_ACTIVE_HIGH),
+ GPIO_LOOKUP_IDX("INT33FC:01", 5, "Panel NC", 5, GPIO_ACTIVE_HIGH),
+ GPIO_LOOKUP_IDX("INT33FC:01", 6, "Panel NC", 6, GPIO_ACTIVE_HIGH),
+ GPIO_LOOKUP_IDX("INT33FC:01", 7, "Panel NC", 7, GPIO_ACTIVE_HIGH),
+ GPIO_LOOKUP_IDX("INT33FC:01", 8, "Panel NC", 8, GPIO_ACTIVE_HIGH),
+ GPIO_LOOKUP_IDX("INT33FC:01", 9, "Panel NC", 9, GPIO_ACTIVE_HIGH),
+ GPIO_LOOKUP_IDX("INT33FC:01", 10, "Panel NC", 10, GPIO_ACTIVE_HIGH),
+ GPIO_LOOKUP_IDX("INT33FC:01", 11, "Panel NC", 11, GPIO_ACTIVE_HIGH),
+ { }
+ },
+};
+
static void vlv_exec_gpio(struct intel_connector *connector,
u8 gpio_source, u8 gpio_index, bool value)
{
struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
- struct gpio_map *map;
- u16 pconf0, padval;
- u32 tmp;
- u8 port;

- if (gpio_index >= ARRAY_SIZE(vlv_gpio_table)) {
- drm_dbg_kms(&dev_priv->drm, "unknown gpio index %u\n",
- gpio_index);
- return;
- }
-
- map = &vlv_gpio_table[gpio_index];
-
- if (connector->panel.vbt.dsi.seq_version >= 3) {
- /* XXX: this assumes vlv_gpio_table only has NC GPIOs. */
- port = IOSF_PORT_GPIO_NC;
- } else {
- if (gpio_source == 0) {
- port = IOSF_PORT_GPIO_NC;
- } else if (gpio_source == 1) {
+ /* XXX: this assumes vlv_gpio_table only has NC GPIOs. */
+ if (connector->panel.vbt.dsi.seq_version < 3) {
+ if (gpio_source == 1) {
drm_dbg_kms(&dev_priv->drm, "SC gpio not supported\n");
return;
- } else {
+ }
+ if (gpio_source > 1) {
drm_dbg_kms(&dev_priv->drm,
"unknown gpio source %u\n", gpio_source);
return;
}
}

- pconf0 = VLV_GPIO_PCONF0(map->base_offset);
- padval = VLV_GPIO_PAD_VAL(map->base_offset);
-
- vlv_iosf_sb_get(dev_priv, BIT(VLV_IOSF_SB_GPIO));
- if (!map->init) {
- /* FIXME: remove constant below */
- vlv_iosf_sb_write(dev_priv, port, pconf0, 0x2000CC00);
- map->init = true;
- }
-
- tmp = 0x4 | value;
- vlv_iosf_sb_write(dev_priv, port, padval, tmp);
- vlv_iosf_sb_put(dev_priv, BIT(VLV_IOSF_SB_GPIO));
+ soc_exec_gpio(connector, "Panel NC", gpio_index, value);
}

static void chv_exec_gpio(struct intel_connector *connector,
@@ -974,6 +929,9 @@ void intel_dsi_vbt_gpio_init(struct intel_dsi *intel_dsi, bool panel_is_on)
struct pinctrl *pinctrl;
int ret;

+ if (IS_VALLEYVIEW(dev_priv))
+ gpiod_add_lookup_table(&vlv_gpio_table);
+
if ((IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) &&
mipi_config->pwm_blc == PPS_BLC_PMIC) {
gpiod_add_lookup_table(&pmic_panel_gpio_table);
@@ -1043,4 +1001,7 @@ void intel_dsi_vbt_gpio_cleanup(struct intel_dsi *intel_dsi)
pinctrl_unregister_mappings(soc_pwm_pinctrl_map);
gpiod_remove_lookup_table(&soc_panel_gpio_table);
}
+
+ if (IS_VALLEYVIEW(dev_priv))
+ gpiod_remove_lookup_table(&vlv_gpio_table);
}
--
2.40.0.1.gaa8946217a0b