drm/nouveau/i2c: use a custom bitbanging delay for the adt7473

This patch adds a way to define a custom delay when scanning for i2c devices
because the adt7473 sometimes doesn't like the default bitbanging udelay.

Signed-off-by: Martin Peres <martin.peres@labri.fr>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

3 files changed, 55 insertions, 33 deletions

diff --git a/drivers/gpu/drm/nouveau/core/include/subdev/i2c.h b/drivers/gpu/drm/nouveau/core/include/subdev/i2c.h
index 7e4e2775f249..9fa5da723871 100644
--- a/drivers/gpu/drm/nouveau/core/include/subdev/i2c.h
+++ b/drivers/gpu/drm/nouveau/core/include/subdev/i2c.h
@@ -60,13 +60,18 @@ void _nouveau_i2c_port_dtor(struct nouveau_object *);
 #define _nouveau_i2c_port_init nouveau_object_init
 #define _nouveau_i2c_port_fini nouveau_object_fini
 
+struct nouveau_i2c_board_info {
+	struct i2c_board_info dev;
+	u8 udelay; /* set to 0 to use the standard delay */
+};
+
 struct nouveau_i2c {
 	struct nouveau_subdev base;
 
 	struct nouveau_i2c_port *(*find)(struct nouveau_i2c *, u8 index);
 	struct nouveau_i2c_port *(*find_type)(struct nouveau_i2c *, u16 type);
 	int (*identify)(struct nouveau_i2c *, int index,
-			const char *what, struct i2c_board_info *,
+			const char *what, struct nouveau_i2c_board_info *,
 			bool (*match)(struct nouveau_i2c_port *,
 				      struct i2c_board_info *));
 	struct list_head ports;
diff --git a/drivers/gpu/drm/nouveau/core/subdev/i2c/base.c b/drivers/gpu/drm/nouveau/core/subdev/i2c/base.c
index 2895c19bb152..041fd5edaebf 100644
--- a/drivers/gpu/drm/nouveau/core/subdev/i2c/base.c
+++ b/drivers/gpu/drm/nouveau/core/subdev/i2c/base.c
@@ -195,7 +195,7 @@ nouveau_i2c_find_type(struct nouveau_i2c *i2c, u16 type)
 
 static int
 nouveau_i2c_identify(struct nouveau_i2c *i2c, int index, const char *what,
-		     struct i2c_board_info *info,
+		     struct nouveau_i2c_board_info *info,
 		     bool (*match)(struct nouveau_i2c_port *,
 				   struct i2c_board_info *))
 {
@@ -208,12 +208,29 @@ nouveau_i2c_identify(struct nouveau_i2c *i2c, int index, const char *what,
 	}
 
 	nv_debug(i2c, "probing %ss on bus: %d\n", what, port->index);
-	for (i = 0; info[i].addr; i++) {
-		if (nv_probe_i2c(port, info[i].addr) &&
-		    (!match || match(port, &info[i]))) {
-			nv_info(i2c, "detected %s: %s\n", what, info[i].type);
+	for (i = 0; info[i].dev.addr; i++) {
+		u8 orig_udelay = 0;
+
+		if ((port->adapter.algo == &i2c_bit_algo) &&
+		    (info[i].udelay != 0)) {
+			struct i2c_algo_bit_data *algo = port->adapter.algo_data;
+			nv_debug(i2c, "using custom udelay %d instead of %d\n",
+			         info[i].udelay, algo->udelay);
+			orig_udelay = algo->udelay;
+			algo->udelay = info[i].udelay;
+		}
+
+		if (nv_probe_i2c(port, info[i].dev.addr) &&
+		    (!match || match(port, &info[i].dev))) {
+			nv_info(i2c, "detected %s: %s\n", what,
+				info[i].dev.type);
 			return i;
 		}
+
+		if (orig_udelay) {
+			struct i2c_algo_bit_data *algo = port->adapter.algo_data;
+			algo->udelay = orig_udelay;
+		}
 	}
 
 	nv_debug(i2c, "no devices found.\n");
diff --git a/drivers/gpu/drm/nouveau/core/subdev/therm/ic.c b/drivers/gpu/drm/nouveau/core/subdev/therm/ic.c
index 8b3adec5fbb1..13b850076443 100644
--- a/drivers/gpu/drm/nouveau/core/subdev/therm/ic.c
+++ b/drivers/gpu/drm/nouveau/core/subdev/therm/ic.c
@@ -55,28 +55,28 @@ probe_monitoring_device(struct nouveau_i2c_port *i2c,
 	return true;
 }
 
-static struct i2c_board_info
+static struct nouveau_i2c_board_info
 nv_board_infos[] = {
-	{ I2C_BOARD_INFO("w83l785ts", 0x2d) },
-	{ I2C_BOARD_INFO("w83781d", 0x2d) },
-	{ I2C_BOARD_INFO("adt7473", 0x2e) },
-	{ I2C_BOARD_INFO("adt7473", 0x2d) },
-	{ I2C_BOARD_INFO("adt7473", 0x2c) },
-	{ I2C_BOARD_INFO("f75375", 0x2e) },
-	{ I2C_BOARD_INFO("lm99", 0x4c) },
-	{ I2C_BOARD_INFO("lm90", 0x4c) },
-	{ I2C_BOARD_INFO("lm90", 0x4d) },
-	{ I2C_BOARD_INFO("adm1021", 0x18) },
-	{ I2C_BOARD_INFO("adm1021", 0x19) },
-	{ I2C_BOARD_INFO("adm1021", 0x1a) },
-	{ I2C_BOARD_INFO("adm1021", 0x29) },
-	{ I2C_BOARD_INFO("adm1021", 0x2a) },
-	{ I2C_BOARD_INFO("adm1021", 0x2b) },
-	{ I2C_BOARD_INFO("adm1021", 0x4c) },
-	{ I2C_BOARD_INFO("adm1021", 0x4d) },
-	{ I2C_BOARD_INFO("adm1021", 0x4e) },
-	{ I2C_BOARD_INFO("lm63", 0x18) },
-	{ I2C_BOARD_INFO("lm63", 0x4e) },
+	{ { I2C_BOARD_INFO("w83l785ts", 0x2d) }, 0 },
+	{ { I2C_BOARD_INFO("w83781d", 0x2d) }, 0  },
+	{ { I2C_BOARD_INFO("adt7473", 0x2e) }, 20  },
+	{ { I2C_BOARD_INFO("adt7473", 0x2d) }, 20  },
+	{ { I2C_BOARD_INFO("adt7473", 0x2c) }, 20  },
+	{ { I2C_BOARD_INFO("f75375", 0x2e) }, 0  },
+	{ { I2C_BOARD_INFO("lm99", 0x4c) }, 0  },
+	{ { I2C_BOARD_INFO("lm90", 0x4c) }, 0  },
+	{ { I2C_BOARD_INFO("lm90", 0x4d) }, 0  },
+	{ { I2C_BOARD_INFO("adm1021", 0x18) }, 0  },
+	{ { I2C_BOARD_INFO("adm1021", 0x19) }, 0  },
+	{ { I2C_BOARD_INFO("adm1021", 0x1a) }, 0  },
+	{ { I2C_BOARD_INFO("adm1021", 0x29) }, 0  },
+	{ { I2C_BOARD_INFO("adm1021", 0x2a) }, 0  },
+	{ { I2C_BOARD_INFO("adm1021", 0x2b) }, 0  },
+	{ { I2C_BOARD_INFO("adm1021", 0x4c) }, 0  },
+	{ { I2C_BOARD_INFO("adm1021", 0x4d) }, 0  },
+	{ { I2C_BOARD_INFO("adm1021", 0x4e) }, 0  },
+	{ { I2C_BOARD_INFO("lm63", 0x18) }, 0  },
+	{ { I2C_BOARD_INFO("lm63", 0x4e) }, 0  },
 	{ }
 };
 
@@ -89,9 +89,9 @@ nouveau_therm_ic_ctor(struct nouveau_therm *therm)
 	struct nvbios_extdev_func extdev_entry;
 
 	if (!nvbios_extdev_find(bios, NVBIOS_EXTDEV_LM89, &extdev_entry)) {
-		struct i2c_board_info board[] = {
-			{ I2C_BOARD_INFO("lm90", extdev_entry.addr >> 1) },
-			{ }
+		struct nouveau_i2c_board_info board[] = {
+		  { { I2C_BOARD_INFO("lm90", extdev_entry.addr >> 1) }, 0},
+		  { }
 		};
 
 		i2c->identify(i2c, NV_I2C_DEFAULT(0), "monitoring device",
@@ -101,9 +101,9 @@ nouveau_therm_ic_ctor(struct nouveau_therm *therm)
 	}
 
 	if (!nvbios_extdev_find(bios, NVBIOS_EXTDEV_ADT7473, &extdev_entry)) {
-		struct i2c_board_info board[] = {
-			{ I2C_BOARD_INFO("adt7473", extdev_entry.addr >> 1) },
-			{ }
+		struct nouveau_i2c_board_info board[] = {
+		  { { I2C_BOARD_INFO("adt7473", extdev_entry.addr >> 1) }, 20 },
+		  { }
 		};
 
 		i2c->identify(i2c, NV_I2C_DEFAULT(0), "monitoring device",