From: Christophe Kerello <christophe.kerello@st.com>
Date: Tue, 17 Oct 2017 09:21:32 +0000 (+0200)
Subject: i2c: stm32f7_i2c: fix data abort
X-Git-Url: http://git.dujemihanovic.xyz/img/static/gitweb.css?a=commitdiff_plain;h=81c484376353251ba13b7ea987a15a896b3d106a;p=u-boot.git

i2c: stm32f7_i2c: fix data abort

As "v" is a local variable in stm32_i2c_choose_solution()
"v" has to be copied into "s" to avoid data abort in
stm32_i2c_compute_timing().

Signed-off-by: Christophe Kerello <christophe.kerello@st.com>
Reviewed-by: Patrick DELAUNAY <patrick.delaunay@st.com>
Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
---

diff --git a/drivers/i2c/stm32f7_i2c.c b/drivers/i2c/stm32f7_i2c.c
index 196f2365ea..346748d433 100644
--- a/drivers/i2c/stm32f7_i2c.c
+++ b/drivers/i2c/stm32f7_i2c.c
@@ -571,6 +571,7 @@ static int stm32_i2c_choose_solution(struct stm32_i2c_setup *setup,
 	u32 dnf_delay;
 	u32 tsync;
 	u16 l, h;
+	bool sol_found = false;
 	int ret = 0;
 
 	af_delay_min = setup->analog_filter ?
@@ -619,14 +620,15 @@ static int stm32_i2c_choose_solution(struct stm32_i2c_setup *setup,
 						clk_error_prev = clk_error;
 						v->scll = l;
 						v->sclh = h;
-						s = v;
+						sol_found = true;
+						memcpy(s, v, sizeof(*s));
 					}
 				}
 			}
 		}
 	}
 
-	if (!s) {
+	if (!sol_found) {
 		pr_err("%s: no solution at all\n", __func__);
 		ret = -EPERM;
 	}
@@ -638,7 +640,7 @@ static int stm32_i2c_compute_timing(struct stm32_i2c_priv *i2c_priv,
 				      struct stm32_i2c_setup *setup,
 				      struct stm32_i2c_timings *output)
 {
-	struct stm32_i2c_timings *v, *_v, *s;
+	struct stm32_i2c_timings *v, *_v, s;
 	struct list_head solutions;
 	int ret;
 
@@ -669,21 +671,20 @@ static int stm32_i2c_compute_timing(struct stm32_i2c_priv *i2c_priv,
 		return -EINVAL;
 	}
 
-	s = NULL;
 	INIT_LIST_HEAD(&solutions);
 	ret = stm32_i2c_compute_solutions(setup, &solutions);
 	if (ret)
 		goto exit;
 
-	ret = stm32_i2c_choose_solution(setup, &solutions, s);
+	ret = stm32_i2c_choose_solution(setup, &solutions, &s);
 	if (ret)
 		goto exit;
 
-	output->presc = s->presc;
-	output->scldel = s->scldel;
-	output->sdadel = s->sdadel;
-	output->scll = s->scll;
-	output->sclh = s->sclh;
+	output->presc = s.presc;
+	output->scldel = s.scldel;
+	output->sdadel = s.sdadel;
+	output->scll = s.scll;
+	output->sclh = s.sclh;
 
 	debug("%s: Presc: %i, scldel: %i, sdadel: %i, scll: %i, sclh: %i\n",
 	      __func__, output->presc,