diff options
Diffstat (limited to 'drivers/gpu/drm/nouveau/core/subdev/i2c')
| -rw-r--r-- | drivers/gpu/drm/nouveau/core/subdev/i2c/aux.c | 212 | ||||
| -rw-r--r-- | drivers/gpu/drm/nouveau/core/subdev/i2c/base.c | 407 | ||||
| -rw-r--r-- | drivers/gpu/drm/nouveau/core/subdev/i2c/bit.c | 230 |
3 files changed, 849 insertions, 0 deletions
diff --git a/drivers/gpu/drm/nouveau/core/subdev/i2c/aux.c b/drivers/gpu/drm/nouveau/core/subdev/i2c/aux.c new file mode 100644 index 000000000000..fe1ebf199ba9 --- /dev/null +++ b/drivers/gpu/drm/nouveau/core/subdev/i2c/aux.c @@ -0,0 +1,212 @@ +/* + * Copyright 2009 Red Hat Inc. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. + * + * Authors: Ben Skeggs + */ + +#include <subdev/i2c.h> + +/****************************************************************************** + * aux channel util functions + *****************************************************************************/ +#define AUX_DBG(fmt, args...) nv_debug(aux, "AUXCH(%d): " fmt, ch, ##args) +#define AUX_ERR(fmt, args...) nv_error(aux, "AUXCH(%d): " fmt, ch, ##args) + +static void +auxch_fini(struct nouveau_i2c *aux, int ch) +{ + nv_mask(aux, 0x00e4e4 + (ch * 0x50), 0x00310000, 0x00000000); +} + +static int +auxch_init(struct nouveau_i2c *aux, int ch) +{ + const u32 unksel = 1; /* nfi which to use, or if it matters.. */ + const u32 ureq = unksel ? 0x00100000 : 0x00200000; + const u32 urep = unksel ? 0x01000000 : 0x02000000; + u32 ctrl, timeout; + + /* wait up to 1ms for any previous transaction to be done... */ + timeout = 1000; + do { + ctrl = nv_rd32(aux, 0x00e4e4 + (ch * 0x50)); + udelay(1); + if (!timeout--) { + AUX_ERR("begin idle timeout 0x%08x", ctrl); + return -EBUSY; + } + } while (ctrl & 0x03010000); + + /* set some magic, and wait up to 1ms for it to appear */ + nv_mask(aux, 0x00e4e4 + (ch * 0x50), 0x00300000, ureq); + timeout = 1000; + do { + ctrl = nv_rd32(aux, 0x00e4e4 + (ch * 0x50)); + udelay(1); + if (!timeout--) { + AUX_ERR("magic wait 0x%08x\n", ctrl); + auxch_fini(aux, ch); + return -EBUSY; + } + } while ((ctrl & 0x03000000) != urep); + + return 0; +} + +static int +auxch_tx(struct nouveau_i2c *aux, int ch, u8 type, u32 addr, u8 *data, u8 size) +{ + u32 ctrl, stat, timeout, retries; + u32 xbuf[4] = {}; + int ret, i; + + AUX_DBG("%d: 0x%08x %d\n", type, addr, size); + + ret = auxch_init(aux, ch); + if (ret) + goto out; + + stat = nv_rd32(aux, 0x00e4e8 + (ch * 0x50)); + if (!(stat & 0x10000000)) { + AUX_DBG("sink not detected\n"); + ret = -ENXIO; + goto out; + } + + if (!(type & 1)) { + memcpy(xbuf, data, size); + for (i = 0; i < 16; i += 4) { + AUX_DBG("wr 0x%08x\n", xbuf[i / 4]); + nv_wr32(aux, 0x00e4c0 + (ch * 0x50) + i, xbuf[i / 4]); + } + } + + ctrl = nv_rd32(aux, 0x00e4e4 + (ch * 0x50)); + ctrl &= ~0x0001f0ff; + ctrl |= type << 12; + ctrl |= size - 1; + nv_wr32(aux, 0x00e4e0 + (ch * 0x50), addr); + + /* retry transaction a number of times on failure... */ + ret = -EREMOTEIO; + for (retries = 0; retries < 32; retries++) { + /* reset, and delay a while if this is a retry */ + nv_wr32(aux, 0x00e4e4 + (ch * 0x50), 0x80000000 | ctrl); + nv_wr32(aux, 0x00e4e4 + (ch * 0x50), 0x00000000 | ctrl); + if (retries) + udelay(400); + + /* transaction request, wait up to 1ms for it to complete */ + nv_wr32(aux, 0x00e4e4 + (ch * 0x50), 0x00010000 | ctrl); + + timeout = 1000; + do { + ctrl = nv_rd32(aux, 0x00e4e4 + (ch * 0x50)); + udelay(1); + if (!timeout--) { + AUX_ERR("tx req timeout 0x%08x\n", ctrl); + goto out; + } + } while (ctrl & 0x00010000); + + /* read status, and check if transaction completed ok */ + stat = nv_mask(aux, 0x00e4e8 + (ch * 0x50), 0, 0); + if (!(stat & 0x000f0f00)) { + ret = 0; + break; + } + + AUX_DBG("%02d 0x%08x 0x%08x\n", retries, ctrl, stat); + } + + if (type & 1) { + for (i = 0; i < 16; i += 4) { + xbuf[i / 4] = nv_rd32(aux, 0x00e4d0 + (ch * 0x50) + i); + AUX_DBG("rd 0x%08x\n", xbuf[i / 4]); + } + memcpy(data, xbuf, size); + } + +out: + auxch_fini(aux, ch); + return ret; +} + +int +nv_rdaux(struct nouveau_i2c_port *auxch, u32 addr, u8 *data, u8 size) +{ + return auxch_tx(auxch->i2c, auxch->drive, 9, addr, data, size); +} + +int +nv_wraux(struct nouveau_i2c_port *auxch, u32 addr, u8 *data, u8 size) +{ + return auxch_tx(auxch->i2c, auxch->drive, 8, addr, data, size); +} + +static int +aux_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) +{ + struct nouveau_i2c_port *auxch = (struct nouveau_i2c_port *)adap; + struct i2c_msg *msg = msgs; + int ret, mcnt = num; + + while (mcnt--) { + u8 remaining = msg->len; + u8 *ptr = msg->buf; + + while (remaining) { + u8 cnt = (remaining > 16) ? 16 : remaining; + u8 cmd; + + if (msg->flags & I2C_M_RD) + cmd = 1; + else + cmd = 0; + + if (mcnt || remaining > 16) + cmd |= 4; /* MOT */ + + ret = auxch_tx(auxch->i2c, auxch->drive, cmd, + msg->addr, ptr, cnt); + if (ret < 0) + return ret; + + ptr += cnt; + remaining -= cnt; + } + + msg++; + } + + return num; +} + +static u32 +aux_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +const struct i2c_algorithm nouveau_i2c_aux_algo = { + .master_xfer = aux_xfer, + .functionality = aux_func +}; diff --git a/drivers/gpu/drm/nouveau/core/subdev/i2c/base.c b/drivers/gpu/drm/nouveau/core/subdev/i2c/base.c new file mode 100644 index 000000000000..3d2c88310f98 --- /dev/null +++ b/drivers/gpu/drm/nouveau/core/subdev/i2c/base.c @@ -0,0 +1,407 @@ +/* + * Copyright 2012 Red Hat Inc. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. + * + * Authors: Ben Skeggs + */ + +#include "core/option.h" + +#include "subdev/i2c.h" +#include "subdev/vga.h" + +int +nv_rdi2cr(struct nouveau_i2c_port *port, u8 addr, u8 reg) +{ + u8 val; + struct i2c_msg msgs[] = { + { .addr = addr, .flags = 0, .len = 1, .buf = ® }, + { .addr = addr, .flags = I2C_M_RD, .len = 1, .buf = &val }, + }; + + int ret = i2c_transfer(&port->adapter, msgs, 2); + if (ret != 2) + return -EIO; + + return val; +} + +int +nv_wri2cr(struct nouveau_i2c_port *port, u8 addr, u8 reg, u8 val) +{ + struct i2c_msg msgs[] = { + { .addr = addr, .flags = 0, .len = 1, .buf = ® }, + { .addr = addr, .flags = 0, .len = 1, .buf = &val }, + }; + + int ret = i2c_transfer(&port->adapter, msgs, 2); + if (ret != 2) + return -EIO; + + return 0; +} + +bool +nv_probe_i2c(struct nouveau_i2c_port *port, u8 addr) +{ + u8 buf[] = { 0 }; + struct i2c_msg msgs[] = { + { + .addr = addr, + .flags = 0, + .len = 1, + .buf = buf, + }, + { + .addr = addr, + .flags = I2C_M_RD, + .len = 1, + .buf = buf, + } + }; + + return i2c_transfer(&port->adapter, msgs, 2) == 2; +} + +static struct nouveau_i2c_port * +nouveau_i2c_find(struct nouveau_i2c *i2c, u8 index) +{ + struct nouveau_bios *bios = nouveau_bios(i2c); + struct nouveau_i2c_port *port; + + if (index == NV_I2C_DEFAULT(0) || + index == NV_I2C_DEFAULT(1)) { + u8 ver, hdr, cnt, len; + u16 i2c = dcb_i2c_table(bios, &ver, &hdr, &cnt, &len); + if (i2c && ver >= 0x30) { + u8 auxidx = nv_ro08(bios, i2c + 4); + if (index == NV_I2C_DEFAULT(0)) + index = (auxidx & 0x0f) >> 0; + else + index = (auxidx & 0xf0) >> 4; + } else { + index = 2; + } + } + + list_for_each_entry(port, &i2c->ports, head) { + if (port->index == index) + break; + } + + if (&port->head == &i2c->ports) + return NULL; + + if (nv_device(i2c)->card_type >= NV_50 && (port->dcb & 0x00000100)) { + u32 reg = 0x00e500, val; + if (port->type == 6) { + reg += port->drive * 0x50; + val = 0x2002; + } else { + reg += ((port->dcb & 0x1e00) >> 9) * 0x50; + val = 0xe001; + } + + /* nfi, but neither auxch or i2c work if it's 1 */ + nv_mask(i2c, reg + 0x0c, 0x00000001, 0x00000000); + /* nfi, but switches auxch vs normal i2c */ + nv_mask(i2c, reg + 0x00, 0x0000f003, val); + } + + return port; +} + +static int +nouveau_i2c_identify(struct nouveau_i2c *i2c, int index, const char *what, + struct i2c_board_info *info, + bool (*match)(struct nouveau_i2c_port *, + struct i2c_board_info *)) +{ + struct nouveau_i2c_port *port = nouveau_i2c_find(i2c, index); + int i; + + if (!port) { + nv_debug(i2c, "no bus when probing %s on %d\n", what, index); + return -ENODEV; + } + + 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); + return i; + } + } + + nv_debug(i2c, "no devices found.\n"); + return -ENODEV; +} + +void +nouveau_i2c_drive_scl(void *data, int state) +{ + struct nouveau_i2c_port *port = data; + + if (port->type == DCB_I2C_NV04_BIT) { + u8 val = nv_rdvgac(port->i2c, 0, port->drive); + if (state) val |= 0x20; + else val &= 0xdf; + nv_wrvgac(port->i2c, 0, port->drive, val | 0x01); + } else + if (port->type == DCB_I2C_NV4E_BIT) { + nv_mask(port->i2c, port->drive, 0x2f, state ? 0x21 : 0x01); + } else + if (port->type == DCB_I2C_NVIO_BIT) { + if (state) port->state |= 0x01; + else port->state &= 0xfe; + nv_wr32(port->i2c, port->drive, 4 | port->state); + } +} + +void +nouveau_i2c_drive_sda(void *data, int state) +{ + struct nouveau_i2c_port *port = data; + + if (port->type == DCB_I2C_NV04_BIT) { + u8 val = nv_rdvgac(port->i2c, 0, port->drive); + if (state) val |= 0x10; + else val &= 0xef; + nv_wrvgac(port->i2c, 0, port->drive, val | 0x01); + } else + if (port->type == DCB_I2C_NV4E_BIT) { + nv_mask(port->i2c, port->drive, 0x1f, state ? 0x11 : 0x01); + } else + if (port->type == DCB_I2C_NVIO_BIT) { + if (state) port->state |= 0x02; + else port->state &= 0xfd; + nv_wr32(port->i2c, port->drive, 4 | port->state); + } +} + +int +nouveau_i2c_sense_scl(void *data) +{ + struct nouveau_i2c_port *port = data; + struct nouveau_device *device = nv_device(port->i2c); + + if (port->type == DCB_I2C_NV04_BIT) { + return !!(nv_rdvgac(port->i2c, 0, port->sense) & 0x04); + } else + if (port->type == DCB_I2C_NV4E_BIT) { + return !!(nv_rd32(port->i2c, port->sense) & 0x00040000); + } else + if (port->type == DCB_I2C_NVIO_BIT) { + if (device->card_type < NV_D0) + return !!(nv_rd32(port->i2c, port->sense) & 0x01); + else + return !!(nv_rd32(port->i2c, port->sense) & 0x10); + } + + return 0; +} + +int +nouveau_i2c_sense_sda(void *data) +{ + struct nouveau_i2c_port *port = data; + struct nouveau_device *device = nv_device(port->i2c); + + if (port->type == DCB_I2C_NV04_BIT) { + return !!(nv_rdvgac(port->i2c, 0, port->sense) & 0x08); + } else + if (port->type == DCB_I2C_NV4E_BIT) { + return !!(nv_rd32(port->i2c, port->sense) & 0x00080000); + } else + if (port->type == DCB_I2C_NVIO_BIT) { + if (device->card_type < NV_D0) + return !!(nv_rd32(port->i2c, port->sense) & 0x02); + else + return !!(nv_rd32(port->i2c, port->sense) & 0x20); + } + + return 0; +} + +static const u32 nv50_i2c_port[] = { + 0x00e138, 0x00e150, 0x00e168, 0x00e180, + 0x00e254, 0x00e274, 0x00e764, 0x00e780, + 0x00e79c, 0x00e7b8 +}; + +static int +nouveau_i2c_ctor(struct nouveau_object *parent, struct nouveau_object *engine, + struct nouveau_oclass *oclass, void *data, u32 size, + struct nouveau_object **pobject) +{ + struct nouveau_device *device = nv_device(parent); + struct nouveau_bios *bios = nouveau_bios(parent); + struct nouveau_i2c_port *port; + struct nouveau_i2c *i2c; + struct dcb_i2c_entry info; + int ret, i = -1; + + ret = nouveau_subdev_create(parent, engine, oclass, 0, + "I2C", "i2c", &i2c); + *pobject = nv_object(i2c); + if (ret) + return ret; + + i2c->find = nouveau_i2c_find; + i2c->identify = nouveau_i2c_identify; + INIT_LIST_HEAD(&i2c->ports); + + while (!dcb_i2c_parse(bios, ++i, &info)) { + if (info.type == DCB_I2C_UNUSED) + continue; + + port = kzalloc(sizeof(*port), GFP_KERNEL); + if (!port) { + nv_error(i2c, "failed port memory alloc at %d\n", i); + break; + } + + port->type = info.type; + switch (port->type) { + case DCB_I2C_NV04_BIT: + port->drive = info.drive; + port->sense = info.sense; + break; + case DCB_I2C_NV4E_BIT: + port->drive = 0x600800 + info.drive; + port->sense = port->drive; + break; + case DCB_I2C_NVIO_BIT: + port->drive = info.drive & 0x0f; + if (device->card_type < NV_D0) { + if (info.drive >= ARRAY_SIZE(nv50_i2c_port)) + break; + port->drive = nv50_i2c_port[port->drive]; + port->sense = port->drive; + } else { + port->drive = 0x00d014 + (port->drive * 0x20); + port->sense = port->drive; + } + break; + case DCB_I2C_NVIO_AUX: + port->drive = info.drive & 0x0f; + port->sense = port->drive; + port->adapter.algo = &nouveau_i2c_aux_algo; + break; + default: + break; + } + + if (!port->adapter.algo && !port->drive) { + nv_error(i2c, "I2C%d: type %d index %x/%x unknown\n", + i, port->type, port->drive, port->sense); + kfree(port); + continue; + } + + snprintf(port->adapter.name, sizeof(port->adapter.name), + "nouveau-%s-%d", device->name, i); + port->adapter.owner = THIS_MODULE; + port->adapter.dev.parent = &device->pdev->dev; + port->i2c = i2c; + port->index = i; + port->dcb = info.data; + i2c_set_adapdata(&port->adapter, i2c); + + if (port->adapter.algo != &nouveau_i2c_aux_algo) { + nouveau_i2c_drive_scl(port, 0); + nouveau_i2c_drive_sda(port, 1); + nouveau_i2c_drive_scl(port, 1); + +#ifdef CONFIG_NOUVEAU_I2C_INTERNAL_DEFAULT + if (nouveau_boolopt(device->cfgopt, "NvI2C", true)) { +#else + if (nouveau_boolopt(device->cfgopt, "NvI2C", false)) { +#endif + port->adapter.algo = &nouveau_i2c_bit_algo; + ret = i2c_add_adapter(&port->adapter); + } else { + port->adapter.algo_data = &port->bit; + port->bit.udelay = 10; + port->bit.timeout = usecs_to_jiffies(2200); + port->bit.data = port; + port->bit.setsda = nouveau_i2c_drive_sda; + port->bit.setscl = nouveau_i2c_drive_scl; + port->bit.getsda = nouveau_i2c_sense_sda; + port->bit.getscl = nouveau_i2c_sense_scl; + ret = i2c_bit_add_bus(&port->adapter); + } + } else { + port->adapter.algo = &nouveau_i2c_aux_algo; + ret = i2c_add_adapter(&port->adapter); + } + + if (ret) { + nv_error(i2c, "I2C%d: failed register: %d\n", i, ret); + kfree(port); + continue; + } + + list_add_tail(&port->head, &i2c->ports); + } + + return 0; +} + +static void +nouveau_i2c_dtor(struct nouveau_object *object) +{ + struct nouveau_i2c *i2c = (void *)object; + struct nouveau_i2c_port *port, *temp; + + list_for_each_entry_safe(port, temp, &i2c->ports, head) { + i2c_del_adapter(&port->adapter); + list_del(&port->head); + kfree(port); + } + + nouveau_subdev_destroy(&i2c->base); +} + +static int +nouveau_i2c_init(struct nouveau_object *object) +{ + struct nouveau_i2c *i2c = (void *)object; + return nouveau_subdev_init(&i2c->base); +} + +static int +nouveau_i2c_fini(struct nouveau_object *object, bool suspend) +{ + struct nouveau_i2c *i2c = (void *)object; + return nouveau_subdev_fini(&i2c->base, suspend); +} + +struct nouveau_oclass +nouveau_i2c_oclass = { + .handle = NV_SUBDEV(I2C, 0x00), + .ofuncs = &(struct nouveau_ofuncs) { + .ctor = nouveau_i2c_ctor, + .dtor = nouveau_i2c_dtor, + .init = nouveau_i2c_init, + .fini = nouveau_i2c_fini, + }, +}; diff --git a/drivers/gpu/drm/nouveau/core/subdev/i2c/bit.c b/drivers/gpu/drm/nouveau/core/subdev/i2c/bit.c new file mode 100644 index 000000000000..1c4c9a5c8e2e --- /dev/null +++ b/drivers/gpu/drm/nouveau/core/subdev/i2c/bit.c @@ -0,0 +1,230 @@ +/* + * Copyright 2012 Red Hat Inc. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. + * + * Authors: Ben Skeggs + */ + +#include "subdev/i2c.h" + +#ifdef CONFIG_NOUVEAU_I2C_INTERNAL +#define T_TIMEOUT 2200000 +#define T_RISEFALL 1000 +#define T_HOLD 5000 + +static inline void +i2c_drive_scl(struct nouveau_i2c_port *port, int state) +{ + nouveau_i2c_drive_scl(port, state); +} + +static inline void +i2c_drive_sda(struct nouveau_i2c_port *port, int state) +{ + nouveau_i2c_drive_sda(port, state); +} + +static inline int +i2c_sense_scl(struct nouveau_i2c_port *port) +{ + return nouveau_i2c_sense_scl(port); +} + +static inline int +i2c_sense_sda(struct nouveau_i2c_port *port) +{ + return nouveau_i2c_sense_sda(port); +} + +static void +i2c_delay(struct nouveau_i2c_port *port, u32 nsec) +{ + udelay((nsec + 500) / 1000); +} + +static bool +i2c_raise_scl(struct nouveau_i2c_port *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_port *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_port *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_port *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_port *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_port *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_port *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_port *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_port *port = (struct nouveau_i2c_port *)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; +} +#else +static int +i2c_bit_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) +{ + return -ENODEV; +} +#endif + +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 +}; |