ACPI: LPSS: Use kstrtol() instead of simple_strtol()

The simple_strtol() function is not reliable in some situation, since
it does not check for the range overflow. Use kstrtol() instead.

While at it, modify the code to avoid evaluating _SEM unnecessarily
if uid_str is NULL or kstrtol() fails to convert that string to a
nonzero number.

Signed-off-by: Liu Shixin <liushixin2@huawei.com>
[ rjw: Check uid right after calling kstrtol() ]
[ rjw: Rewrite subject and changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c
index ca742f1..894b7e6 100644 (file)
--- a/drivers/acpi/acpi_lpss.c
+++ b/drivers/acpi/acpi_lpss.c
@@ -186,13 +186,12 @@ static void byt_i2c_setup(struct lpss_private_data *pdata)
        long uid = 0;
 
        /* Expected to always be true, but better safe then sorry */
-       if (uid_str)
-               uid = simple_strtol(uid_str, NULL, 10);
-
-       /* Detect I2C bus shared with PUNIT and ignore its d3 status */
-       status = acpi_evaluate_integer(handle, "_SEM", NULL, &shared_host);
-       if (ACPI_SUCCESS(status) && shared_host && uid)
-               pmc_atom_d3_mask &= ~(BIT_LPSS2_F1_I2C1 << (uid - 1));
+       if (uid_str && !kstrtol(uid_str, 10, &uid) && uid) {
+               /* Detect I2C bus shared with PUNIT and ignore its d3 status */
+               status = acpi_evaluate_integer(handle, "_SEM", NULL, &shared_host);
+               if (ACPI_SUCCESS(status) && shared_host)
+                       pmc_atom_d3_mask &= ~(BIT_LPSS2_F1_I2C1 << (uid - 1));
+       }
 
        lpss_deassert_reset(pdata);