linux-kernel - [PATCH v2 6/7] drm/i915/dsi: Replace poking of CHV GPIOs behind the driver's back

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Message-Id: <20231024155739.3861342-7-andriy.shevchenko@linux.intel.com>
Date:   Tue, 24 Oct 2023 18:57:38 +0300
From:   Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To:     Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Jani Nikula <jani.nikula@...el.com>,
        intel-gfx@...ts.freedesktop.org, dri-devel@...ts.freedesktop.org,
        linux-kernel@...r.kernel.org
Cc:     Jani Nikula <jani.nikula@...ux.intel.com>,
        Joonas Lahtinen <joonas.lahtinen@...ux.intel.com>,
        Rodrigo Vivi <rodrigo.vivi@...el.com>,
        Tvrtko Ursulin <tvrtko.ursulin@...ux.intel.com>,
        David Airlie <airlied@...il.com>,
        Daniel Vetter <daniel@...ll.ch>,
        Hans de Goede <hdegoede@...hat.com>
Subject: [PATCH v2 6/7] drm/i915/dsi: Replace poking of CHV GPIOs behind the driver's back

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 0bd50d719b00 ("pinctrl:
cherryview: prevent concurrent access to GPIO controllers") for
the details. Taking all this into consideration replace the hack
with proper GPIO APIs being used.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
---
 drivers/gpu/drm/i915/display/intel_dsi_vbt.c | 47 +++++---------------
 1 file changed, 10 insertions(+), 37 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_dsi_vbt.c b/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
index 8fc82aceae14..a393ddaff0dd 100644
--- a/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
+++ b/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
@@ -66,19 +66,6 @@ struct i2c_adapter_lookup {
 #define CHV_GPIO_IDX_START_SW		100
 #define CHV_GPIO_IDX_START_SE		198
 
-#define CHV_VBT_MAX_PINS_PER_FMLY	15
-
-#define CHV_GPIO_PAD_CFG0(f, i)		(0x4400 + (f) * 0x400 + (i) * 8)
-#define  CHV_GPIO_GPIOEN		(1 << 15)
-#define  CHV_GPIO_GPIOCFG_GPIO		(0 << 8)
-#define  CHV_GPIO_GPIOCFG_GPO		(1 << 8)
-#define  CHV_GPIO_GPIOCFG_GPI		(2 << 8)
-#define  CHV_GPIO_GPIOCFG_HIZ		(3 << 8)
-#define  CHV_GPIO_GPIOTXSTATE(state)	((!!(state)) << 1)
-
-#define CHV_GPIO_PAD_CFG1(f, i)		(0x4400 + (f) * 0x400 + (i) * 8 + 4)
-#define  CHV_GPIO_CFGLOCK		(1 << 31)
-
 /* ICL DSI Display GPIO Pins */
 #define  ICL_GPIO_DDSP_HPD_A		0
 #define  ICL_GPIO_L_VDDEN_1		1
@@ -279,23 +266,21 @@ static void chv_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);
-	u16 cfg0, cfg1;
-	u16 family_num;
-	u8 port;
 
 	if (connector->panel.vbt.dsi.seq_version >= 3) {
 		if (gpio_index >= CHV_GPIO_IDX_START_SE) {
 			/* XXX: it's unclear whether 255->57 is part of SE. */
-			gpio_index -= CHV_GPIO_IDX_START_SE;
-			port = CHV_IOSF_PORT_GPIO_SE;
+			soc_exec_opaque_gpio(connector, "INT33FF:03", "Panel SE",
+					     gpio_index - CHV_GPIO_IDX_START_SW, value);
 		} else if (gpio_index >= CHV_GPIO_IDX_START_SW) {
-			gpio_index -= CHV_GPIO_IDX_START_SW;
-			port = CHV_IOSF_PORT_GPIO_SW;
+			soc_exec_opaque_gpio(connector, "INT33FF:00", "Panel SW",
+					     gpio_index - CHV_GPIO_IDX_START_SW, value);
 		} else if (gpio_index >= CHV_GPIO_IDX_START_E) {
-			gpio_index -= CHV_GPIO_IDX_START_E;
-			port = CHV_IOSF_PORT_GPIO_E;
+			soc_exec_opaque_gpio(connector, "INT33FF:02", "Panel E",
+					     gpio_index - CHV_GPIO_IDX_START_E, value);
 		} else {
-			port = CHV_IOSF_PORT_GPIO_N;
+			soc_exec_opaque_gpio(connector, "INT33FF:01", "Panel N",
+					     gpio_index - CHV_GPIO_IDX_START_N, value);
 		}
 	} else {
 		/* XXX: The spec is unclear about CHV GPIO on seq v2 */
@@ -312,21 +297,9 @@ static void chv_exec_gpio(struct intel_connector *connector,
 			return;
 		}
 
-		port = CHV_IOSF_PORT_GPIO_N;
+		soc_exec_opaque_gpio(connector, "INT33FF:01", "Panel N",
+				     gpio_index - CHV_GPIO_IDX_START_N, value);
 	}
-
-	family_num = gpio_index / CHV_VBT_MAX_PINS_PER_FMLY;
-	gpio_index = gpio_index % CHV_VBT_MAX_PINS_PER_FMLY;
-
-	cfg0 = CHV_GPIO_PAD_CFG0(family_num, gpio_index);
-	cfg1 = CHV_GPIO_PAD_CFG1(family_num, gpio_index);
-
-	vlv_iosf_sb_get(dev_priv, BIT(VLV_IOSF_SB_GPIO));
-	vlv_iosf_sb_write(dev_priv, port, cfg1, 0);
-	vlv_iosf_sb_write(dev_priv, port, cfg0,
-			  CHV_GPIO_GPIOEN | CHV_GPIO_GPIOCFG_GPO |
-			  CHV_GPIO_GPIOTXSTATE(value));
-	vlv_iosf_sb_put(dev_priv, BIT(VLV_IOSF_SB_GPIO));
 }
 
 static void bxt_exec_gpio(struct intel_connector *connector,
-- 
2.40.0.1.gaa8946217a0b