From a9bab25556f142c696c660f4be54dba9808403d2 Mon Sep 17 00:00:00 2001 From: Marco Felsch Date: Tue, 17 Sep 2019 16:44:48 +0200 Subject: [PATCH] usb: usb251xb: simplify reset helper Currently the reset handler was always called to deassert the reset line because assert the line was done during probe. Now if we want to support pm by turn of the supply we need to call this routine twice and the i2c_lock_bus is done twice too. To simplify that we can drop the state and just do a reset in one go. So a future pm operation don't need to lock the i2c bus twice. Signed-off-by: Marco Felsch Reviewed-by: Richard Leitner Tested-by: Richard Leitner Link: https://lore.kernel.org/r/20190917144449.32739-4-m.felsch@pengutronix.de Signed-off-by: Greg Kroah-Hartman --- drivers/usb/misc/usb251xb.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) diff --git a/drivers/usb/misc/usb251xb.c b/drivers/usb/misc/usb251xb.c index 05819167604d..bc031d33f433 100644 --- a/drivers/usb/misc/usb251xb.c +++ b/drivers/usb/misc/usb251xb.c @@ -263,20 +263,19 @@ static int usb251x_check_gpio_chip(struct usb251xb *hub) } #endif -static void usb251xb_reset(struct usb251xb *hub, int state) +static void usb251xb_reset(struct usb251xb *hub) { if (!hub->gpio_reset) return; i2c_lock_bus(hub->i2c->adapter, I2C_LOCK_SEGMENT); - gpiod_set_value_cansleep(hub->gpio_reset, state); + gpiod_set_value_cansleep(hub->gpio_reset, 1); + usleep_range(1, 10); /* >=1us RESET_N asserted */ + gpiod_set_value_cansleep(hub->gpio_reset, 0); /* wait for hub recovery/stabilization */ - if (!state) - usleep_range(500, 750); /* >=500us at power on */ - else - usleep_range(1, 10); /* >=1us at power down */ + usleep_range(500, 750); /* >=500us after RESET_N deasserted */ i2c_unlock_bus(hub->i2c->adapter, I2C_LOCK_SEGMENT); } @@ -294,7 +293,7 @@ static int usb251xb_connect(struct usb251xb *hub) i2c_wb[0] = 0x01; i2c_wb[1] = USB251XB_STATUS_COMMAND_ATTACH; - usb251xb_reset(hub, 0); + usb251xb_reset(hub); err = i2c_smbus_write_i2c_block_data(hub->i2c, USB251XB_ADDR_STATUS_COMMAND, 2, i2c_wb); @@ -344,7 +343,7 @@ static int usb251xb_connect(struct usb251xb *hub) i2c_wb[USB251XB_ADDR_PORT_MAP_7] = hub->port_map7; i2c_wb[USB251XB_ADDR_STATUS_COMMAND] = USB251XB_STATUS_COMMAND_ATTACH; - usb251xb_reset(hub, 0); + usb251xb_reset(hub); /* write registers */ for (i = 0; i < (USB251XB_I2C_REG_SZ / USB251XB_I2C_WRITE_SZ); i++) { -- 2.45.2