There is no "disabled" port 0. So, don't even try to initialize/scan it, etc. This saves a bit of time when initializing the driver, since it avoids a 50ms timeout waiting for a device to respond on a port that doesn't even exist.
Similarly, don't initialize the "reserved" port 7, either.
Tested on Sandybridge (gen 6, PCH == CougarPoint) hardware.
Signed-off-by: Daniel Kurtz djkurtz@chromium.org --- drivers/gpu/drm/i915/i915_reg.h | 1 - drivers/gpu/drm/i915/intel_i2c.c | 64 +++++++++++++++++-------------------- 2 files changed, 29 insertions(+), 36 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index 56af0df..89cace2 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -699,7 +699,6 @@ #define GMBUS_PORT_DPB 5 /* SDVO, HDMIB */ #define GMBUS_PORT_DPD 6 /* HDMID */ #define GMBUS_PORT_RESERVED 7 /* 7 reserved */ -#define GMBUS_NUM_PORTS 8 #define GMBUS1 0x5104 /* command/status */ #define GMBUS_SW_CLR_INT (1<<31) #define GMBUS_SW_RDY (1<<30) diff --git a/drivers/gpu/drm/i915/intel_i2c.c b/drivers/gpu/drm/i915/intel_i2c.c index 87a3abf..f53f525 100644 --- a/drivers/gpu/drm/i915/intel_i2c.c +++ b/drivers/gpu/drm/i915/intel_i2c.c @@ -35,6 +35,20 @@ #include "i915_drm.h" #include "i915_drv.h"
+struct gmbus_port { + const char *name; + int reg; +}; + +static const struct gmbus_port gmbus_ports[] = { + { "ssc", GPIOB }, + { "vga", GPIOA }, + { "panel", GPIOC }, + { "dpc", GPIOD }, + { "dpb", GPIOE }, + { "dpd", GPIOF }, +}; + /* Intel GPIO access functions */
#define I2C_RISEFALL_TIME 20 @@ -150,32 +164,22 @@ static void set_data(void *data, int state_high) static struct i2c_adapter * intel_gpio_create(struct drm_i915_private *dev_priv, u32 pin) { - static const int map_pin_to_reg[] = { - 0, - GPIOB, - GPIOA, - GPIOC, - GPIOD, - GPIOE, - GPIOF, - 0, - }; struct intel_gpio *gpio;
- if (pin >= ARRAY_SIZE(map_pin_to_reg) || !map_pin_to_reg[pin]) - return NULL; + pin -= 1; /* NB: -1 to map pin pair to gmbus array index */ + BUG_ON(pin >= ARRAY_SIZE(gmbus_ports));
gpio = kzalloc(sizeof(struct intel_gpio), GFP_KERNEL); if (gpio == NULL) return NULL;
- gpio->reg = map_pin_to_reg[pin]; + gpio->reg = gmbus_ports[pin].reg; if (HAS_PCH_SPLIT(dev_priv->dev)) gpio->reg += PCH_GPIOA - GPIOA; gpio->dev_priv = dev_priv;
snprintf(gpio->adapter.name, sizeof(gpio->adapter.name), - "i915 GPIO%c", "?BACDEF?"[pin]); + "i915 GPIO%c", "BACDEF"[pin]); gpio->adapter.owner = THIS_MODULE; gpio->adapter.algo_data = &gpio->algo; gpio->adapter.dev.parent = &dev_priv->dev->pdev->dev; @@ -369,33 +373,22 @@ static const struct i2c_algorithm gmbus_algorithm = { */ int intel_setup_gmbus(struct drm_device *dev) { - static const char *names[GMBUS_NUM_PORTS] = { - "disabled", - "ssc", - "vga", - "panel", - "dpc", - "dpb", - "dpd", - "reserved", - }; struct drm_i915_private *dev_priv = dev->dev_private; int ret, i;
- dev_priv->gmbus = kcalloc(sizeof(struct intel_gmbus), GMBUS_NUM_PORTS, - GFP_KERNEL); + dev_priv->gmbus = kcalloc(sizeof(struct intel_gmbus), + ARRAY_SIZE(gmbus_ports), GFP_KERNEL); if (dev_priv->gmbus == NULL) return -ENOMEM;
- for (i = 0; i < GMBUS_NUM_PORTS; i++) { + for (i = 0; i < ARRAY_SIZE(gmbus_ports); i++) { struct intel_gmbus *bus = &dev_priv->gmbus[i]; + u32 port = i + 1; /* +1 to map gmbus index to pin pair */
bus->adapter.owner = THIS_MODULE; bus->adapter.class = I2C_CLASS_DDC; - snprintf(bus->adapter.name, - sizeof(bus->adapter.name), - "i915 gmbus %s", - names[i]); + snprintf(bus->adapter.name, sizeof(bus->adapter.name), + "i915 gmbus %s", gmbus_ports[i].name);
bus->adapter.dev.parent = &dev->pdev->dev; bus->adapter.algo_data = dev_priv; @@ -406,10 +399,10 @@ int intel_setup_gmbus(struct drm_device *dev) goto err;
/* By default use a conservative clock rate */ - bus->reg0 = i | GMBUS_RATE_100KHZ; + bus->reg0 = port | GMBUS_RATE_100KHZ;
/* XXX force bit banging until GMBUS is fully debugged */ - bus->force_bit = intel_gpio_create(dev_priv, i); + bus->force_bit = intel_gpio_create(dev_priv, port); }
intel_i2c_reset(dev_priv->dev); @@ -429,7 +422,8 @@ err: struct i2c_adapter *intel_gmbus_get_adapter(struct drm_i915_private *dev_priv, unsigned pin) { - BUG_ON(pin >= GMBUS_NUM_PORTS); + pin -= 1; /* NB: -1 to map pin pair to gmbus array index */ + BUG_ON(pin >= ARRAY_SIZE(gmbus_ports)); return &dev_priv->gmbus[pin].adapter; }
@@ -467,7 +461,7 @@ void intel_teardown_gmbus(struct drm_device *dev) if (dev_priv->gmbus == NULL) return;
- for (i = 0; i < GMBUS_NUM_PORTS; i++) { + for (i = 0; i < ARRAY_SIZE(gmbus_ports); i++) { struct intel_gmbus *bus = &dev_priv->gmbus[i]; if (bus->force_bit) { i2c_del_adapter(bus->force_bit);