diff options
author | Dave Airlie <airlied@redhat.com> | 2008-07-09 14:53:47 +1000 |
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committer | Dave Airlie <airlied@redhat.com> | 2008-07-09 14:53:47 +1000 |
commit | 2556341f8baf0e0b7b5f7843135e43e662751af0 (patch) | |
tree | 84b591787aa036959e56c490b38dbf9e191c76dd /linux-core/nv50_i2c.c | |
parent | 38a5f6686cd38d5204e240f30006538bcf70f5ac (diff) | |
parent | 0b7d9a97bd2383fe4382fc1b1b266542020f0c4e (diff) |
Merge remote branch 'origin/modesetting-101' into modesetting-gem
Diffstat (limited to 'linux-core/nv50_i2c.c')
-rw-r--r-- | linux-core/nv50_i2c.c | 400 |
1 files changed, 400 insertions, 0 deletions
diff --git a/linux-core/nv50_i2c.c b/linux-core/nv50_i2c.c new file mode 100644 index 00000000..30e317c5 --- /dev/null +++ b/linux-core/nv50_i2c.c @@ -0,0 +1,400 @@ +/* + * Copyright (C) 2008 Maarten Maathuis. + * All Rights Reserved. + * + * 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 (including the + * next paragraph) 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 OWNER(S) AND/OR ITS SUPPLIERS 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. + * + */ + +/* This is largely a clone from xorg i2c functions, as i had serious trouble getting an i2c_bit_algo adaptor running. */ + +#include "nv50_i2c.h" + +static uint32_t nv50_i2c_port(int index) +{ + uint32_t port = 0; + + switch (index) { + case 0: + port = NV50_PCONNECTOR_I2C_PORT_0; + break; + case 1: + port = NV50_PCONNECTOR_I2C_PORT_1; + break; + case 2: + port = NV50_PCONNECTOR_I2C_PORT_2; + break; + case 3: + port = NV50_PCONNECTOR_I2C_PORT_3; + break; + case 4: + port = NV50_PCONNECTOR_I2C_PORT_4; + break; + case 5: + port = NV50_PCONNECTOR_I2C_PORT_5; + break; + default: + break; + } + + if (!port) { + DRM_ERROR("Invalid i2c port, returning 0.\n"); + BUG(); + } + + return port; +} + +static void nv50_i2c_set_bits(struct nv50_i2c_channel *chan, int clock_high, int data_high) +{ + struct drm_nouveau_private *dev_priv = chan->dev->dev_private; + uint32_t port = nv50_i2c_port(chan->index); + + if (!port) + return; + + NV_WRITE(port, 4 | (data_high << 1) | clock_high); +} + +static void nv50_i2c_get_bits(struct nv50_i2c_channel *chan, int *clock_high, int *data_high) +{ + struct drm_nouveau_private *dev_priv = chan->dev->dev_private; + uint32_t port = nv50_i2c_port(chan->index); + uint32_t val; + + if (!port) + return; + + val = NV_READ(port); + + if (val & 1) + *clock_high = 1; + else + *clock_high = 0; + + if (val & 2) + *data_high = 1; + else + *data_high = 0; +} + +static bool nv50_i2c_raise_clock(struct nv50_i2c_channel *chan, int data) +{ + int i, clock; + + nv50_i2c_set_bits(chan, 1, data); + udelay(2); + + for (i = 2200; i > 0; i -= 2) { + nv50_i2c_get_bits(chan, &clock, &data); + if (clock) + return true; + udelay(2); + } + + printk("a timeout occured in nv50_i2c_raise_clock\n"); + + return false; +} + +static bool nv50_i2c_start(struct nv50_i2c_channel *chan) +{ + if (!nv50_i2c_raise_clock(chan, 1)) + return false; + + nv50_i2c_set_bits(chan, 1, 0); + udelay(5); + + nv50_i2c_set_bits(chan, 0, 0); + udelay(5); + + return true; +} + +static void nv50_i2c_stop(struct nv50_i2c_channel *chan) +{ + nv50_i2c_set_bits(chan, 0, 0); + udelay(2); + + nv50_i2c_set_bits(chan, 1, 0); + udelay(5); + + nv50_i2c_set_bits(chan, 1, 1); + udelay(5); +} + +static bool nv50_i2c_write_bit(struct nv50_i2c_channel *chan, int data) +{ + bool rval; + + nv50_i2c_set_bits(chan, 0, data); + udelay(2); + + rval = nv50_i2c_raise_clock(chan, data); + udelay(5); + + nv50_i2c_set_bits(chan, 0, data); + udelay(5); + + return rval; +} + +static bool nv50_i2c_read_bit(struct nv50_i2c_channel *chan, int *data) +{ + bool rval; + int clock; + + rval = nv50_i2c_raise_clock(chan, 1); + udelay(5); + + nv50_i2c_get_bits(chan, &clock, data); + udelay(5); + + nv50_i2c_set_bits(chan, 0, 1); + udelay(5); + + return rval; +} + +static bool nv50_i2c_write_byte(struct nv50_i2c_channel *chan, uint8_t byte) +{ + bool rval; + int i, clock, data; + + for (i = 7; i >= 0; i--) + if (!nv50_i2c_write_bit(chan, (byte >> i) & 1)) + return false; + + nv50_i2c_set_bits(chan, 0, 1); + udelay(5); + + rval = nv50_i2c_raise_clock(chan, 1); + + if (rval) { + for (i = 40; i > 0; i -= 2) { + udelay(2); + nv50_i2c_get_bits(chan, &clock, &data); + if (data == 0) + break; + } + + if (i <= 0) { + printk("a timeout occured in nv50_i2c_write_byte\n"); + rval = false; + } + } + + nv50_i2c_set_bits(chan, 0, 1); + udelay(5); + + return rval; +} + +static bool nv50_i2c_read_byte(struct nv50_i2c_channel *chan, uint8_t *byte, bool last) +{ + int i, bit; + + nv50_i2c_set_bits(chan, 0, 1); + udelay(5); + + *byte = 0; + + for (i = 7; i >= 0; i--) { + if (nv50_i2c_read_bit(chan, &bit)) { + if (bit) + *byte |= (1 << i); + } else { + return false; + } + } + + if (!nv50_i2c_write_bit(chan, last ? 1 : 0)) + return false; + + return true; +} + +/* only 7 bits addresses. */ +static bool nv50_i2c_address(struct nv50_i2c_channel *chan, uint8_t address, bool write) +{ + if (nv50_i2c_start(chan)) { + uint8_t real_addr = (address << 1); + if (!write) + real_addr |= 1; + + if (nv50_i2c_write_byte(chan, real_addr)) + return true; + + /* failure, so issue stop */ + nv50_i2c_stop(chan); + } + + return false; +} + +static bool nv50_i2c_read(struct nv50_i2c_channel *chan, uint8_t address, uint8_t *buffer, uint32_t length) +{ + int i, j; + bool rval, last; + + /* retries */ + for (i = 0; i < 4; i++) { + rval = nv50_i2c_address(chan, address, false); + if (!rval) + return false; + + for (j = 0; j < length; j++) { + last = false; + if (j == (length - 1)) + last = true; + rval = nv50_i2c_read_byte(chan, &buffer[j], last); + if (!rval) { + nv50_i2c_stop(chan); + break; + } + } + + nv50_i2c_stop(chan); + + /* done */ + if (rval) + break; + } + + if (!rval) + printk("nv50_i2c_read failed\n"); + + return rval; +} + +static bool nv50_i2c_write(struct nv50_i2c_channel *chan, uint8_t address, uint8_t *buffer, uint32_t length) +{ + int i, j; + bool rval; + + /* retries */ + for (i = 0; i < 4; i++) { + rval = nv50_i2c_address(chan, address, true); + if (!rval) + return false; + + for (j = 0; j < length; j++) { + rval = nv50_i2c_write_byte(chan, buffer[j]); + if (!rval) { + break; + } + } + + nv50_i2c_stop(chan); + + /* done */ + if (rval) + break; + } + + if (!rval) + printk("nv50_i2c_write failed\n"); + + return rval; +} + +static int nv50_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num) +{ + struct nv50_i2c_channel *chan = i2c_get_adapdata(i2c_adap); + bool rval; + int i; + + for (i = 0; i < num; i++) { + if (msgs[i].flags & I2C_M_RD) { /* read */ + rval = nv50_i2c_read(chan, msgs[i].addr, msgs[i].buf, msgs[i].len); + } else { /* write */ + rval = nv50_i2c_write(chan, msgs[i].addr, msgs[i].buf, msgs[i].len); + } + + if (!rval) + break; + } + + if (rval) + return i; + else + return -EINVAL; +} + +static u32 nv50_i2c_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C; +} + +static const struct i2c_algorithm nv50_i2c_algo = { + .master_xfer = nv50_i2c_xfer, + .functionality = nv50_i2c_functionality, +}; + +static int nv50_i2c_register_bus(struct i2c_adapter *adap) +{ + adap->algo = &nv50_i2c_algo; + + adap->timeout = 40; + adap->retries = 4; + + return i2c_add_adapter(adap); +} + +#define I2C_HW_B_NOUVEAU 0x010030 +struct nv50_i2c_channel *nv50_i2c_channel_create(struct drm_device *dev, uint32_t index) +{ + struct nv50_i2c_channel *chan; + + chan = kzalloc(sizeof(struct nv50_i2c_channel), GFP_KERNEL); + + if (!chan) + goto out; + + DRM_INFO("Creating i2c bus with index %d\n", index); + + chan->dev = dev; + chan->index = index; + snprintf(chan->adapter.name, I2C_NAME_SIZE, "nv50 i2c %d", index); + chan->adapter.owner = THIS_MODULE; + chan->adapter.id = I2C_HW_B_NOUVEAU; + chan->adapter.dev.parent = &dev->pdev->dev; + + i2c_set_adapdata(&chan->adapter, chan); + + if (nv50_i2c_register_bus(&chan->adapter)) + goto out; + + return chan; + +out: + kfree(chan); + return NULL; +} + +void nv50_i2c_channel_destroy(struct nv50_i2c_channel *chan) +{ + if (!chan) + return; + + i2c_del_adapter(&chan->adapter); + kfree(chan); +} |