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authorLinus Walleij <linus.walleij@linaro.org>2017-01-30 16:39:20 +0300
committerLinus Walleij <linus.walleij@linaro.org>2017-01-30 16:39:20 +0300
commit7f36f5d11cda050b118f76d774151427a18d15ef (patch)
tree9d4fa3b830785b767525a5e6a065fe4297cd8112 /drivers/i2c/busses/i2c-piix4.c
parent2b24efa8e5c5042b0f126c09622b3e9e3c86a4fa (diff)
parent566cf877a1fcb6d6dc0126b076aad062054c2637 (diff)
downloadlinux-7f36f5d11cda050b118f76d774151427a18d15ef.tar.xz
Merge tag 'v4.10-rc6' into devel
Linux 4.10-rc6 Resolved conflicts in: drivers/pinctrl/pinctrl-amd.c drivers/pinctrl/samsung/pinctrl-exynos.c
Diffstat (limited to 'drivers/i2c/busses/i2c-piix4.c')
-rw-r--r--drivers/i2c/busses/i2c-piix4.c22
1 files changed, 22 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-piix4.c b/drivers/i2c/busses/i2c-piix4.c
index c2268cdf38e8..e34d82e79b98 100644
--- a/drivers/i2c/busses/i2c-piix4.c
+++ b/drivers/i2c/busses/i2c-piix4.c
@@ -585,10 +585,29 @@ static s32 piix4_access_sb800(struct i2c_adapter *adap, u16 addr,
u8 command, int size, union i2c_smbus_data *data)
{
struct i2c_piix4_adapdata *adapdata = i2c_get_adapdata(adap);
+ unsigned short piix4_smba = adapdata->smba;
+ int retries = MAX_TIMEOUT;
+ int smbslvcnt;
u8 smba_en_lo;
u8 port;
int retval;
+ /* Request the SMBUS semaphore, avoid conflicts with the IMC */
+ smbslvcnt = inb_p(SMBSLVCNT);
+ do {
+ outb_p(smbslvcnt | 0x10, SMBSLVCNT);
+
+ /* Check the semaphore status */
+ smbslvcnt = inb_p(SMBSLVCNT);
+ if (smbslvcnt & 0x10)
+ break;
+
+ usleep_range(1000, 2000);
+ } while (--retries);
+ /* SMBus is still owned by the IMC, we give up */
+ if (!retries)
+ return -EBUSY;
+
mutex_lock(&piix4_mutex_sb800);
outb_p(piix4_port_sel_sb800, SB800_PIIX4_SMB_IDX);
@@ -606,6 +625,9 @@ static s32 piix4_access_sb800(struct i2c_adapter *adap, u16 addr,
mutex_unlock(&piix4_mutex_sb800);
+ /* Release the semaphore */
+ outb_p(smbslvcnt | 0x20, SMBSLVCNT);
+
return retval;
}