From d579478cee228bdc0029a0c12a1f6a63ea9d1c77 Mon Sep 17 00:00:00 2001 From: Sasha Finkelstein Date: Thu, 18 Dec 2025 10:15:23 -0800 Subject: [PATCH] Input: apple_z2 - fix reading incorrect reports after exiting sleep Under certain conditions (more prevalent after a suspend/resume cycle), the touchscreen controller can send the "boot complete" interrupt before it actually finished booting. In those cases, attempting to read touch data resuls in a stream of "not ready" messages being read and interpreted as a touch report. Check that the response is in fact a touch report and discard it otherwise. Reported-by: pitust Closes: https://oftc.catirclogs.org/asahi/2025-12-17#34878715; Fixes: 471a92f8a21a ("Input: apple_z2 - add a driver for Apple Z2 touchscreens") Signed-off-by: Sasha Finkelstein Link: https://patch.msgid.link/20251218-z2-init-fix-v1-1-48e3aa239caf@gmail.com Cc: stable@vger.kernel.org Signed-off-by: Dmitry Torokhov --- drivers/input/touchscreen/apple_z2.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/input/touchscreen/apple_z2.c b/drivers/input/touchscreen/apple_z2.c index 0de161eae59a0..271ababf0ad55 100644 --- a/drivers/input/touchscreen/apple_z2.c +++ b/drivers/input/touchscreen/apple_z2.c @@ -21,6 +21,7 @@ #define APPLE_Z2_TOUCH_STARTED 3 #define APPLE_Z2_TOUCH_MOVED 4 #define APPLE_Z2_CMD_READ_INTERRUPT_DATA 0xEB +#define APPLE_Z2_REPLY_INTERRUPT_DATA 0xE1 #define APPLE_Z2_HBPP_CMD_BLOB 0x3001 #define APPLE_Z2_FW_MAGIC 0x5746325A #define LOAD_COMMAND_INIT_PAYLOAD 0 @@ -142,6 +143,9 @@ static int apple_z2_read_packet(struct apple_z2 *z2) if (error) return error; + if (z2->rx_buf[0] != APPLE_Z2_REPLY_INTERRUPT_DATA) + return 0; + pkt_len = (get_unaligned_le16(z2->rx_buf + 1) + 8) & 0xfffffffc; error = spi_read(z2->spidev, z2->rx_buf, pkt_len); -- 2.47.3