diff options
Diffstat (limited to 'drivers/hid/hid-mcp2221.c')
| -rw-r--r-- | drivers/hid/hid-mcp2221.c | 200 |
1 files changed, 165 insertions, 35 deletions
diff --git a/drivers/hid/hid-mcp2221.c b/drivers/hid/hid-mcp2221.c index 72883e0ce757..33603b019f97 100644 --- a/drivers/hid/hid-mcp2221.c +++ b/drivers/hid/hid-mcp2221.c @@ -18,6 +18,7 @@ #include <linux/i2c.h> #include <linux/gpio/driver.h> #include <linux/iio/iio.h> +#include <linux/minmax.h> #include "hid-ids.h" /* Commands codes in a raw output report */ @@ -49,11 +50,33 @@ enum { MCP2221_I2C_MASK_ADDR_NACK = 0x40, MCP2221_I2C_WRADDRL_SEND = 0x21, MCP2221_I2C_ADDR_NACK = 0x25, + MCP2221_I2C_READ_PARTIAL = 0x54, MCP2221_I2C_READ_COMPL = 0x55, MCP2221_ALT_F_NOT_GPIOV = 0xEE, MCP2221_ALT_F_NOT_GPIOD = 0xEF, }; +/* MCP SRAM read offsets cmd: MCP2221_GET_SRAM_SETTINGS */ +enum { + MCP2221_SRAM_RD_GP0 = 22, + MCP2221_SRAM_RD_GP1 = 23, + MCP2221_SRAM_RD_GP2 = 24, + MCP2221_SRAM_RD_GP3 = 25, +}; + +/* MCP SRAM write offsets cmd: MCP2221_SET_SRAM_SETTINGS */ +enum { + MCP2221_SRAM_WR_GP_ENA_ALTER = 7, + MCP2221_SRAM_WR_GP0 = 8, + MCP2221_SRAM_WR_GP1 = 9, + MCP2221_SRAM_WR_GP2 = 10, + MCP2221_SRAM_WR_GP3 = 11, +}; + +#define MCP2221_SRAM_GP_DESIGN_MASK 0x07 +#define MCP2221_SRAM_GP_DIRECTION_MASK 0x08 +#define MCP2221_SRAM_GP_VALUE_MASK 0x10 + /* MCP GPIO direction encoding */ enum { MCP2221_DIR_OUT = 0x00, @@ -187,6 +210,25 @@ static int mcp_cancel_last_cmd(struct mcp2221 *mcp) return mcp_send_data_req_status(mcp, mcp->txbuf, 8); } +/* Check if the last command succeeded or failed and return the result. + * If the command did fail, cancel that command which will free the i2c bus. + */ +static int mcp_chk_last_cmd_status_free_bus(struct mcp2221 *mcp) +{ + int ret; + + ret = mcp_chk_last_cmd_status(mcp); + if (ret) { + /* The last command was a failure. + * Send a cancel which will also free the bus. + */ + usleep_range(980, 1000); + mcp_cancel_last_cmd(mcp); + } + + return ret; +} + static int mcp_set_i2c_speed(struct mcp2221 *mcp) { int ret; @@ -221,10 +263,7 @@ static int mcp_i2c_write(struct mcp2221 *mcp, idx = 0; sent = 0; - if (msg->len < 60) - len = msg->len; - else - len = 60; + len = min(msg->len, 60); do { mcp->txbuf[0] = type; @@ -241,7 +280,7 @@ static int mcp_i2c_write(struct mcp2221 *mcp, usleep_range(980, 1000); if (last_status) { - ret = mcp_chk_last_cmd_status(mcp); + ret = mcp_chk_last_cmd_status_free_bus(mcp); if (ret) return ret; } @@ -251,10 +290,7 @@ static int mcp_i2c_write(struct mcp2221 *mcp, break; idx = idx + len; - if ((msg->len - sent) < 60) - len = msg->len - sent; - else - len = 60; + len = min(msg->len - sent, 60); /* * Testing shows delay is needed between successive writes @@ -278,6 +314,7 @@ static int mcp_i2c_smbus_read(struct mcp2221 *mcp, { int ret; u16 total_len; + int retries = 0; mcp->txbuf[0] = type; if (msg) { @@ -301,20 +338,31 @@ static int mcp_i2c_smbus_read(struct mcp2221 *mcp, mcp->rxbuf_idx = 0; do { + /* Wait for the data to be read by the device */ + usleep_range(980, 1000); + memset(mcp->txbuf, 0, 4); mcp->txbuf[0] = MCP2221_I2C_GET_DATA; ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1); - if (ret) - return ret; - - ret = mcp_chk_last_cmd_status(mcp); - if (ret) - return ret; - - usleep_range(980, 1000); + if (ret) { + if (retries < 5) { + /* The data wasn't ready to read. + * Wait a bit longer and try again. + */ + usleep_range(90, 100); + retries++; + } else { + return ret; + } + } else { + retries = 0; + } } while (mcp->rxbuf_idx < total_len); + usleep_range(980, 1000); + ret = mcp_chk_last_cmd_status_free_bus(mcp); + return ret; } @@ -328,11 +376,6 @@ static int mcp_i2c_xfer(struct i2c_adapter *adapter, mutex_lock(&mcp->lock); - /* Setting speed before every transaction is required for mcp2221 */ - ret = mcp_set_i2c_speed(mcp); - if (ret) - goto exit; - if (num == 1) { if (msgs->flags & I2C_M_RD) { ret = mcp_i2c_smbus_read(mcp, msgs, MCP2221_I2C_RD_DATA, @@ -417,9 +460,7 @@ static int mcp_smbus_write(struct mcp2221 *mcp, u16 addr, if (last_status) { usleep_range(980, 1000); - ret = mcp_chk_last_cmd_status(mcp); - if (ret) - return ret; + ret = mcp_chk_last_cmd_status_free_bus(mcp); } return ret; @@ -437,10 +478,6 @@ static int mcp_smbus_xfer(struct i2c_adapter *adapter, u16 addr, mutex_lock(&mcp->lock); - ret = mcp_set_i2c_speed(mcp); - if (ret) - goto exit; - switch (size) { case I2C_SMBUS_QUICK: @@ -586,6 +623,80 @@ static const struct i2c_algorithm mcp_i2c_algo = { }; #if IS_REACHABLE(CONFIG_GPIOLIB) +static int mcp_gpio_read_sram(struct mcp2221 *mcp) +{ + int ret; + + memset(mcp->txbuf, 0, 64); + mcp->txbuf[0] = MCP2221_GET_SRAM_SETTINGS; + + mutex_lock(&mcp->lock); + ret = mcp_send_data_req_status(mcp, mcp->txbuf, 64); + mutex_unlock(&mcp->lock); + + return ret; +} + +/* + * If CONFIG_IIO is not enabled, check for the gpio pins + * if they are in gpio mode. For the ones which are not + * in gpio mode, set them into gpio mode. + */ +static int mcp2221_check_gpio_pinfunc(struct mcp2221 *mcp) +{ + int i; + int needgpiofix = 0; + int ret; + + if (IS_ENABLED(CONFIG_IIO)) + return 0; + + ret = mcp_gpio_read_sram(mcp); + if (ret) + return ret; + + for (i = 0; i < MCP_NGPIO; i++) { + if ((mcp->mode[i] & MCP2221_SRAM_GP_DESIGN_MASK) != 0x0) { + dev_warn(&mcp->hdev->dev, + "GPIO %d not in gpio mode\n", i); + needgpiofix = 1; + } + } + + if (!needgpiofix) + return 0; + + /* + * Set all bytes to 0, so Bit 7 is not set. The chip + * only changes content of a register when bit 7 is set. + */ + memset(mcp->txbuf, 0, 64); + mcp->txbuf[0] = MCP2221_SET_SRAM_SETTINGS; + + /* + * Set bit 7 in MCP2221_SRAM_WR_GP_ENA_ALTER to enable + * loading of a new set of gpio settings to GP SRAM + */ + mcp->txbuf[MCP2221_SRAM_WR_GP_ENA_ALTER] = 0x80; + for (i = 0; i < MCP_NGPIO; i++) { + if ((mcp->mode[i] & MCP2221_SRAM_GP_DESIGN_MASK) == 0x0) { + /* write current GPIO mode */ + mcp->txbuf[MCP2221_SRAM_WR_GP0 + i] = mcp->mode[i]; + } else { + /* pin is not in gpio mode, set it to input mode */ + mcp->txbuf[MCP2221_SRAM_WR_GP0 + i] = 0x08; + dev_warn(&mcp->hdev->dev, + "Set GPIO mode for gpio pin %d!\n", i); + } + } + + mutex_lock(&mcp->lock); + ret = mcp_send_data_req_status(mcp, mcp->txbuf, 64); + mutex_unlock(&mcp->lock); + + return ret; +} + static int mcp_gpio_get(struct gpio_chip *gc, unsigned int offset) { @@ -603,10 +714,10 @@ static int mcp_gpio_get(struct gpio_chip *gc, return ret; } -static void mcp_gpio_set(struct gpio_chip *gc, - unsigned int offset, int value) +static int mcp_gpio_set(struct gpio_chip *gc, unsigned int offset, int value) { struct mcp2221 *mcp = gpiochip_get_data(gc); + int ret; memset(mcp->txbuf, 0, 18); mcp->txbuf[0] = MCP2221_GPIO_SET; @@ -617,8 +728,10 @@ static void mcp_gpio_set(struct gpio_chip *gc, mcp->txbuf[mcp->gp_idx] = !!value; mutex_lock(&mcp->lock); - mcp_send_data_req_status(mcp, mcp->txbuf, 18); + ret = mcp_send_data_req_status(mcp, mcp->txbuf, 18); mutex_unlock(&mcp->lock); + + return ret; } static int mcp_gpio_dir_set(struct mcp2221 *mcp, @@ -791,7 +904,12 @@ static int mcp2221_raw_event(struct hid_device *hdev, mcp->status = -EIO; break; } - if (data[2] == MCP2221_I2C_READ_COMPL) { + if (data[2] == MCP2221_I2C_READ_COMPL || + data[2] == MCP2221_I2C_READ_PARTIAL) { + if (!mcp->rxbuf || mcp->rxbuf_idx < 0 || data[3] > 60) { + mcp->status = -EINVAL; + break; + } buf = mcp->rxbuf; memcpy(&buf[mcp->rxbuf_idx], &data[4], data[3]); mcp->rxbuf_idx = mcp->rxbuf_idx + data[3]; @@ -922,9 +1040,11 @@ static void mcp2221_hid_unregister(void *ptr) /* This is needed to be sure hid_hw_stop() isn't called twice by the subsystem */ static void mcp2221_remove(struct hid_device *hdev) { +#if IS_REACHABLE(CONFIG_IIO) struct mcp2221 *mcp = hid_get_drvdata(hdev); cancel_delayed_work_sync(&mcp->init_work); +#endif } #if IS_REACHABLE(CONFIG_IIO) @@ -1024,7 +1144,7 @@ static int mcp_iio_channels(struct mcp2221 *mcp) break; default: continue; - }; + } chan->type = IIO_VOLTAGE; chan->indexed = 1; @@ -1142,27 +1262,35 @@ static int mcp2221_probe(struct hid_device *hdev, if (ret) return ret; + hid_device_io_start(hdev); + /* Set I2C bus clock diviser */ if (i2c_clk_freq > 400) i2c_clk_freq = 400; if (i2c_clk_freq < 50) i2c_clk_freq = 50; mcp->cur_i2c_clk_div = (12000000 / (i2c_clk_freq * 1000)) - 3; + ret = mcp_set_i2c_speed(mcp); + if (ret) { + hid_err(hdev, "can't set i2c speed: %d\n", ret); + return ret; + } mcp->adapter.owner = THIS_MODULE; mcp->adapter.class = I2C_CLASS_HWMON; mcp->adapter.algo = &mcp_i2c_algo; mcp->adapter.retries = 1; mcp->adapter.dev.parent = &hdev->dev; + ACPI_COMPANION_SET(&mcp->adapter.dev, ACPI_COMPANION(hdev->dev.parent)); snprintf(mcp->adapter.name, sizeof(mcp->adapter.name), "MCP2221 usb-i2c bridge"); + i2c_set_adapdata(&mcp->adapter, mcp); ret = devm_i2c_add_adapter(&hdev->dev, &mcp->adapter); if (ret) { hid_err(hdev, "can't add usb-i2c adapter: %d\n", ret); return ret; } - i2c_set_adapdata(&mcp->adapter, mcp); #if IS_REACHABLE(CONFIG_GPIOLIB) /* Setup GPIO chip */ @@ -1184,6 +1312,8 @@ static int mcp2221_probe(struct hid_device *hdev, ret = devm_gpiochip_add_data(&hdev->dev, mcp->gc, mcp); if (ret) return ret; + + mcp2221_check_gpio_pinfunc(mcp); #endif #if IS_REACHABLE(CONFIG_IIO) |