diff options
Diffstat (limited to 'drivers/hid/hid-mcp2221.c')
| -rw-r--r-- | drivers/hid/hid-mcp2221.c | 108 |
1 files changed, 100 insertions, 8 deletions
diff --git a/drivers/hid/hid-mcp2221.c b/drivers/hid/hid-mcp2221.c index 6c0ac14f11a6..fcfe9370a887 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 */ @@ -55,6 +56,27 @@ enum { 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, @@ -241,10 +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; @@ -271,10 +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 @@ -607,6 +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) { @@ -1218,6 +1308,8 @@ 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) |