From 281a02ece2245254f415172306a8577dca96eda3 Mon Sep 17 00:00:00 2001 From: Ben Skeggs Date: Fri, 4 May 2012 14:38:49 +1000 Subject: [PATCH] drm/nouveau/i2c: resume use of i2c-algo-bit, rather than custom stack Previous issues with i2c-algo-bit have now been resolved. Signed-off-by: Ben Skeggs Signed-off-by: Dave Airlie --- drivers/gpu/drm/nouveau/nouveau_i2c.c | 199 ++++----------------------------- drivers/gpu/drm/nouveau/nouveau_i2c.h | 1 + 2 files changed, 22 insertions(+), 178 deletions(-) diff --git a/drivers/gpu/drm/nouveau/nouveau_i2c.c b/drivers/gpu/drm/nouveau/nouveau_i2c.c index e2be95a..77e5646 100644 --- a/drivers/gpu/drm/nouveau/nouveau_i2c.c +++ b/drivers/gpu/drm/nouveau/nouveau_i2c.c @@ -29,10 +29,6 @@ #include "nouveau_i2c.h" #include "nouveau_hw.h" -#define T_TIMEOUT 2200000 -#define T_RISEFALL 1000 -#define T_HOLD 5000 - static void i2c_drive_scl(void *data, int state) { @@ -113,175 +109,6 @@ i2c_sense_sda(void *data) return 0; } -static void -i2c_delay(struct nouveau_i2c_chan *port, u32 nsec) -{ - udelay((nsec + 500) / 1000); -} - -static bool -i2c_raise_scl(struct nouveau_i2c_chan *port) -{ - u32 timeout = T_TIMEOUT / T_RISEFALL; - - i2c_drive_scl(port, 1); - do { - i2c_delay(port, T_RISEFALL); - } while (!i2c_sense_scl(port) && --timeout); - - return timeout != 0; -} - -static int -i2c_start(struct nouveau_i2c_chan *port) -{ - int ret = 0; - - port->state = i2c_sense_scl(port); - port->state |= i2c_sense_sda(port) << 1; - if (port->state != 3) { - i2c_drive_scl(port, 0); - i2c_drive_sda(port, 1); - if (!i2c_raise_scl(port)) - ret = -EBUSY; - } - - i2c_drive_sda(port, 0); - i2c_delay(port, T_HOLD); - i2c_drive_scl(port, 0); - i2c_delay(port, T_HOLD); - return ret; -} - -static void -i2c_stop(struct nouveau_i2c_chan *port) -{ - i2c_drive_scl(port, 0); - i2c_drive_sda(port, 0); - i2c_delay(port, T_RISEFALL); - - i2c_drive_scl(port, 1); - i2c_delay(port, T_HOLD); - i2c_drive_sda(port, 1); - i2c_delay(port, T_HOLD); -} - -static int -i2c_bitw(struct nouveau_i2c_chan *port, int sda) -{ - i2c_drive_sda(port, sda); - i2c_delay(port, T_RISEFALL); - - if (!i2c_raise_scl(port)) - return -ETIMEDOUT; - i2c_delay(port, T_HOLD); - - i2c_drive_scl(port, 0); - i2c_delay(port, T_HOLD); - return 0; -} - -static int -i2c_bitr(struct nouveau_i2c_chan *port) -{ - int sda; - - i2c_drive_sda(port, 1); - i2c_delay(port, T_RISEFALL); - - if (!i2c_raise_scl(port)) - return -ETIMEDOUT; - i2c_delay(port, T_HOLD); - - sda = i2c_sense_sda(port); - - i2c_drive_scl(port, 0); - i2c_delay(port, T_HOLD); - return sda; -} - -static int -i2c_get_byte(struct nouveau_i2c_chan *port, u8 *byte, bool last) -{ - int i, bit; - - *byte = 0; - for (i = 7; i >= 0; i--) { - bit = i2c_bitr(port); - if (bit < 0) - return bit; - *byte |= bit << i; - } - - return i2c_bitw(port, last ? 1 : 0); -} - -static int -i2c_put_byte(struct nouveau_i2c_chan *port, u8 byte) -{ - int i, ret; - for (i = 7; i >= 0; i--) { - ret = i2c_bitw(port, !!(byte & (1 << i))); - if (ret < 0) - return ret; - } - - ret = i2c_bitr(port); - if (ret == 1) /* nack */ - ret = -EIO; - return ret; -} - -static int -i2c_addr(struct nouveau_i2c_chan *port, struct i2c_msg *msg) -{ - u32 addr = msg->addr << 1; - if (msg->flags & I2C_M_RD) - addr |= 1; - return i2c_put_byte(port, addr); -} - -static int -i2c_bit_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) -{ - struct nouveau_i2c_chan *port = (struct nouveau_i2c_chan *)adap; - struct i2c_msg *msg = msgs; - int ret = 0, mcnt = num; - - while (!ret && mcnt--) { - u8 remaining = msg->len; - u8 *ptr = msg->buf; - - ret = i2c_start(port); - if (ret == 0) - ret = i2c_addr(port, msg); - - if (msg->flags & I2C_M_RD) { - while (!ret && remaining--) - ret = i2c_get_byte(port, ptr++, !remaining); - } else { - while (!ret && remaining--) - ret = i2c_put_byte(port, *ptr++); - } - - msg++; - } - - i2c_stop(port); - return (ret < 0) ? ret : num; -} - -static u32 -i2c_bit_func(struct i2c_adapter *adap) -{ - return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; -} - -const struct i2c_algorithm nouveau_i2c_bit_algo = { - .master_xfer = i2c_bit_xfer, - .functionality = i2c_bit_func -}; - static const uint32_t nv50_i2c_port[] = { 0x00e138, 0x00e150, 0x00e168, 0x00e180, 0x00e254, 0x00e274, 0x00e764, 0x00e780, @@ -384,12 +211,10 @@ nouveau_i2c_init(struct drm_device *dev) case 0: /* NV04:NV50 */ port->drive = entry[0]; port->sense = entry[1]; - port->adapter.algo = &nouveau_i2c_bit_algo; break; case 4: /* NV4E */ port->drive = 0x600800 + entry[1]; port->sense = port->drive; - port->adapter.algo = &nouveau_i2c_bit_algo; break; case 5: /* NV50- */ port->drive = entry[0] & 0x0f; @@ -402,7 +227,6 @@ nouveau_i2c_init(struct drm_device *dev) port->drive = 0x00d014 + (port->drive * 0x20); port->sense = port->drive; } - port->adapter.algo = &nouveau_i2c_bit_algo; break; case 6: /* NV50- DP AUX */ port->drive = entry[0]; @@ -413,7 +237,7 @@ nouveau_i2c_init(struct drm_device *dev) break; } - if (!port->adapter.algo) { + if (!port->adapter.algo && !port->drive) { NV_ERROR(dev, "I2C%d: type %d index %x/%x unknown\n", i, port->type, port->drive, port->sense); kfree(port); @@ -429,7 +253,26 @@ nouveau_i2c_init(struct drm_device *dev) port->dcb = ROM32(entry[0]); i2c_set_adapdata(&port->adapter, i2c); - ret = i2c_add_adapter(&port->adapter); + if (port->adapter.algo != &nouveau_dp_i2c_algo) { + port->adapter.algo_data = &port->bit; + port->bit.udelay = 10; + port->bit.timeout = usecs_to_jiffies(2200); + port->bit.data = port; + port->bit.setsda = i2c_drive_sda; + port->bit.setscl = i2c_drive_scl; + port->bit.getsda = i2c_sense_sda; + port->bit.getscl = i2c_sense_scl; + + i2c_drive_scl(port, 0); + i2c_drive_sda(port, 1); + i2c_drive_scl(port, 1); + + ret = i2c_bit_add_bus(&port->adapter); + } else { + port->adapter.algo = &nouveau_dp_i2c_algo; + ret = i2c_add_adapter(&port->adapter); + } + if (ret) { NV_ERROR(dev, "I2C%d: failed register: %d\n", i, ret); kfree(port); diff --git a/drivers/gpu/drm/nouveau/nouveau_i2c.h b/drivers/gpu/drm/nouveau/nouveau_i2c.h index 4d2e4e9..1d08389 100644 --- a/drivers/gpu/drm/nouveau/nouveau_i2c.h +++ b/drivers/gpu/drm/nouveau/nouveau_i2c.h @@ -34,6 +34,7 @@ struct nouveau_i2c_chan { struct i2c_adapter adapter; struct drm_device *dev; + struct i2c_algo_bit_data bit; struct list_head head; u8 index; u8 type; -- 1.7.7.6