From e896be5ad1017aa710f8b979036a43d3e5b2f38d Mon Sep 17 00:00:00 2001 From: Russell King Date: Mon, 27 Apr 2020 19:49:32 +0100 Subject: [PATCH] i2c: pxa: fix i2c_pxa_wait_bus_not_busy() boundary condition Fix i2c_pxa_wait_bus_not_busy()'s boundary conditions, so that a coincidental success and timeout results in the function returning success. Signed-off-by: Russell King Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-pxa.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c index 7aa35de..c1e50c0 100644 --- a/drivers/i2c/busses/i2c-pxa.c +++ b/drivers/i2c/busses/i2c-pxa.c @@ -416,19 +416,26 @@ static void i2c_pxa_abort(struct pxa_i2c *i2c) static int i2c_pxa_wait_bus_not_busy(struct pxa_i2c *i2c) { int timeout = DEF_TIMEOUT; + u32 isr; - while (timeout-- && readl(_ISR(i2c)) & (ISR_IBB | ISR_UB)) { - if ((readl(_ISR(i2c)) & ISR_SAD) != 0) + while (1) { + isr = readl(_ISR(i2c)); + if (!(isr & (ISR_IBB | ISR_UB))) + return 0; + + if (isr & ISR_SAD) timeout += 4; + if (!timeout--) + break; + msleep(2); show_state(i2c); } - if (timeout < 0) - show_state(i2c); + show_state(i2c); - return timeout < 0 ? I2C_RETRY : 0; + return I2C_RETRY; } static int i2c_pxa_wait_master(struct pxa_i2c *i2c) -- 2.7.4