immortalwrt-mt798x/target/linux/generic/backport-5.4/820-v5.8-i2c-pxa-use-master-abort-for-device-probes.patch
Russell King 714199ec34 kernel: backport v5.8 i2c-pxa updates
Add i2c-pxa updates queued for v5.8, which add bus recovery to this
driver; this is needed for the uDPU platform.

Signed-off-by: Russell King <linux@armlinux.org.uk>
2020-05-21 12:55:31 +02:00

41 lines
1.1 KiB
Diff

From: Russell King <rmk+kernel@armlinux.org.uk>
Bcc: linux@mail.armlinux.org.uk
Subject: [PATCH 6/7] i2c: pxa: use master-abort for device probes
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Use master-abort to send the stop condition after an address cycle
rather than resetting the controller.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
drivers/i2c/busses/i2c-pxa.c | 10 ++--------
1 file changed, 2 insertions(+), 8 deletions(-)
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index a72d07bdb793..0e194d6cd1b5 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -940,14 +940,8 @@ static void i2c_pxa_irq_txempty(struct pxa_i2c *i2c, u32 isr)
icr &= ~ICR_ALDIE;
icr |= ICR_START | ICR_TB;
} else {
- if (i2c->msg->len == 0) {
- /*
- * Device probes have a message length of zero
- * and need the bus to be reset before it can
- * be used again.
- */
- i2c_pxa_reset(i2c);
- }
+ if (i2c->msg->len == 0)
+ icr |= ICR_MA;
i2c_pxa_master_complete(i2c, 0);
}
--
2.20.1