diff options
| author | Simon Glass <sjg@chromium.org> | 2023-05-05 01:54:56 +0300 |
|---|---|---|
| committer | Bin Meng <bmeng@tinylab.org> | 2023-05-11 05:25:29 +0300 |
| commit | d8062e950367fab0f219a889e8f2fbfade90108c (patch) | |
| tree | 7fa183802fef4f9a00c57c9106524e68b9743086 | |
| parent | 7a187a89fd96e8f2344b47b7fd4d3a686da66f55 (diff) | |
| download | u-boot-d8062e950367fab0f219a889e8f2fbfade90108c.tar.xz | |
input: Flush the keyboard buffer before resetting it
If U-Boot is not the first-stage bootloader the keyboard may already be
set up. Make sure to flush any data before trying to reset it. This
avoids a long timeout / hang.
Add some comments and a log category while we are here.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
| -rw-r--r-- | drivers/input/i8042.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/drivers/input/i8042.c b/drivers/input/i8042.c index 3563dc9883..e6070ca015 100644 --- a/drivers/input/i8042.c +++ b/drivers/input/i8042.c @@ -6,6 +6,8 @@ /* i8042.c - Intel 8042 keyboard driver routines */ +#define LOG_CATEGORY UCLASS_KEYBOARD + #include <common.h> #include <dm.h> #include <env.h> @@ -54,6 +56,14 @@ static unsigned char ext_key_map[] = { 0x00 /* map end */ }; +/** + * kbd_input_empty() - Wait until the keyboard is ready for a command + * + * Checks the IBF flag (input buffer full), waiting for it to indicate that + * any previous command has been processed. + * + * Return: true if ready, false if it timed out + */ static int kbd_input_empty(void) { int kbd_timeout = KBD_TIMEOUT * 1000; @@ -64,6 +74,12 @@ static int kbd_input_empty(void) return kbd_timeout != -1; } +/** + * kbd_output_full() - Wait until the keyboard has data available + * + * Checks the OBF flag (output buffer full), waiting for it to indicate that + * a response to a previous command is available + */ static int kbd_output_full(void) { int kbd_timeout = KBD_TIMEOUT * 1000; @@ -127,6 +143,9 @@ static int kbd_reset(int quirk) { int config; + if (!kbd_input_empty()) + goto err; + /* controller self test */ if (kbd_cmd_read(CMD_SELF_TEST) != KBC_TEST_OK) goto err; |