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i2c: pxa: clear all master action bits in i2c_pxa_stop_message()

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[ Upstream commit e81c979f4e071d516aa27cf5a0c3939da00dc1ca ]

If we timeout during a message transfer, the control register may
contain bits that cause an action to be set. Read-modify-writing the
register leaving these bits set may trigger the hardware to attempt
one of these actions unintentionally.

Always clear these bits when cleaning up after a message or after
a timeout.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Russell King 2020-05-06 10:36:38 +01:00 • committed by Greg Kroah-Hartman
parent 9ecdbfee2d
commit 3018d81cd9
1 changed files with 2 additions and 4 deletions
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6
drivers/i2c/busses/i2c-pxa.c
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@ -709,11 +709,9 @@ static inline void i2c_pxa_stop_message(struct pxa_i2c *i2c)
{ {
u32 icr; u32 icr;
/* /* Clear the START, STOP, ACK, TB and MA flags */
* Clear the STOP and ACK flags
*/
icr = readl(_ICR(i2c)); icr = readl(_ICR(i2c));
icr &= ~(ICR_STOP | ICR_ACKNAK); icr &= ~(ICR_START | ICR_STOP | ICR_ACKNAK | ICR_TB | ICR_MA);
writel(icr, _ICR(i2c)); writel(icr, _ICR(i2c));
} }