Re: [PATCH 2/2] Input: add MStar msg26xx touchscreen driver
flat view
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Date: 2021-01-21 07:07:27
Also in:
linux-devicetree, lkml
Hi Vincent, On Wed, Jan 20, 2021 at 07:01:08PM +0100, Vincent Knecht wrote:
quoted hunk ↗ jump to hunk
+struct packet { + u8 y_high : 4; + u8 x_high : 4;
This will not work on big endian devices as order of bitfields changes. I'd recommended treating contact packet as sequence of bytes and parse, i.e. x = ((buf[0] & 0x0f) << 8) | buf[1]; x = ((buf[0] & 0xf0) << 4) | buf[2]; ...
quoted hunk ↗ jump to hunk
+ u8 x_low; + u8 y_low; + u8 pressure; +}; + + +static void mstar_power_on(struct msg26xx_ts_data *msg26xx) +{ + gpiod_set_value(msg26xx->reset_gpiod, 0); + mdelay(10); + gpiod_set_value(msg26xx->reset_gpiod, 1); + mdelay(FIRMWARE_ON_DELAY);
I am pretty sure this is incorrect. You are saying that you release the reset line, wait a bit, and then assert it. gpiod is a logical API, with 0 being inactive and 1 being active, and here you want to activate the reset line, wait appropriate time, release it, and wait for the device to initialize. What does the datasheet say about reset GPIO polarity? Thanks. -- Dmitry