diff options
author | Dino Li <Dino.Li@ite.com.tw> | 2017-10-31 14:59:50 +0800 |
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committer | chrome-bot <chrome-bot@chromium.org> | 2017-10-31 21:49:24 -0700 |
commit | 73d0ed0b794b13ceff5620b5c15ba7a3760d1f35 (patch) | |
tree | 3083fa0ba743eb5d70e90c15394c7d479f51c756 /driver/usb_mux_it5205.c | |
parent | b979c8ade3c46d67ef739bfe22361b8fc5db6b34 (diff) | |
download | chrome-ec-73d0ed0b794b13ceff5620b5c15ba7a3760d1f35.tar.gz |
driver: add IT5205 mux driver
Add support the ITE IT5205 Type-C USB alternate mode mux.
BRANCH=none
BUG=none
TEST=1. Successfully verify chip ID.
2. Verify set_mux() and get_mux() functions set and return
consistent values.
3. The mux control register setting as expected after set_mux().
Change-Id: I9ff066dc9e74683df1371b70290e2aeaa86cb96b
Signed-off-by: Dino Li <Dino.Li@ite.com.tw>
Reviewed-on: https://chromium-review.googlesource.com/741211
Reviewed-by: Shawn N <shawnn@chromium.org>
Diffstat (limited to 'driver/usb_mux_it5205.c')
-rw-r--r-- | driver/usb_mux_it5205.c | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/driver/usb_mux_it5205.c b/driver/usb_mux_it5205.c new file mode 100644 index 0000000000..c6b9a91778 --- /dev/null +++ b/driver/usb_mux_it5205.c @@ -0,0 +1,120 @@ +/* Copyright 2017 The Chromium OS Authors. All rights reserved. + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + * + * ITE IT5205 Type-C USB alternate mode mux. + */ + +#include "common.h" +#include "console.h" +#include "i2c.h" +#include "usb_mux.h" +#include "usb_mux_it5205.h" +#include "util.h" + +#define MUX_STATE_DP_USB_MASK (MUX_USB_ENABLED | MUX_DP_ENABLED) + +static int it5205_read(int i2c_addr, uint8_t reg, int *val) +{ + return i2c_read8(I2C_PORT_USB_MUX, i2c_addr, reg, val); +} + +static int it5205_write(int i2c_addr, uint8_t reg, uint8_t val) +{ + return i2c_write8(I2C_PORT_USB_MUX, i2c_addr, reg, val); +} + +struct mux_chip_id_t { + uint8_t chip_id; + uint8_t reg; +}; + +static const struct mux_chip_id_t mux_chip_id_verify[] = { + { '5', IT5205_REG_CHIP_ID3}, + { '2', IT5205_REG_CHIP_ID2}, + { '0', IT5205_REG_CHIP_ID1}, + { '5', IT5205_REG_CHIP_ID0}, +}; + +static int it5205_init(int i2c_addr) +{ + int i, val, ret; + + /* bit[0]: mux power on, bit[7-1]: reserved. */ + ret = it5205_write(i2c_addr, IT5205_REG_MUXPDR, 0); + if (ret) + return ret; + /* Verify chip ID registers. */ + for (i = 0; i < ARRAY_SIZE(mux_chip_id_verify); i++) { + ret = it5205_read(i2c_addr, mux_chip_id_verify[i].reg, &val); + if (ret) + return ret; + + if (val != mux_chip_id_verify[i].chip_id) + return EC_ERROR_UNKNOWN; + } + + return EC_SUCCESS; +} + +/* Writes control register to set switch mode */ +static int it5205_set_mux(int i2c_addr, mux_state_t mux_state) +{ + uint8_t reg; + + switch (mux_state & MUX_STATE_DP_USB_MASK) { + case MUX_USB_ENABLED: + reg = IT5205_USB; + break; + case MUX_DP_ENABLED: + reg = IT5205_DP; + break; + case MUX_STATE_DP_USB_MASK: + reg = IT5205_DP_USB; + break; + default: + reg = 0; + break; + } + + if (mux_state & MUX_POLARITY_INVERTED) + reg |= IT5205_POLARITY_INVERTED; + + return it5205_write(i2c_addr, IT5205_REG_MUXCR, reg); +} + +/* Reads control register and updates mux_state accordingly */ +static int it5205_get_mux(int i2c_addr, mux_state_t *mux_state) +{ + int reg, ret; + + ret = it5205_read(i2c_addr, IT5205_REG_MUXCR, ®); + if (ret) + return ret; + + switch (reg & IT5205_DP_USB_CTRL_MASK) { + case IT5205_USB: + *mux_state = MUX_USB_ENABLED; + break; + case IT5205_DP: + *mux_state = MUX_DP_ENABLED; + break; + case IT5205_DP_USB: + *mux_state = MUX_STATE_DP_USB_MASK; + break; + default: + *mux_state = 0; + break; + } + + if (reg & IT5205_POLARITY_INVERTED) + *mux_state |= MUX_POLARITY_INVERTED; + + return EC_SUCCESS; +} + +const struct usb_mux_driver it5205_usb_mux_driver = { + .init = it5205_init, + .set = it5205_set_mux, + .get = it5205_get_mux, +}; |