bnx2x: fix I2C non-respondent issue

When I2C is not responding it's usually due to a previous
unexpected reset during I2C operation. We release it by
powering down and up the SFP+ module.

Signed-off-by: Yaniv Rosner <yaniv.rosner@broadcom.com>
Signed-off-by: Yuval Mintz <yuvalmin@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 29 insertions, 23 deletions

diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_link.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_link.c
index a3fb7215cd89..51d7ab6a0276 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_link.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_link.c
@@ -40,6 +40,7 @@
 #define I2C_BSC0                        0
 #define I2C_BSC1                        1
 #define I2C_WA_RETRY_CNT                3
+#define I2C_WA_PWR_ITER                 (I2C_WA_RETRY_CNT - 1)
 #define MCPR_IMC_COMMAND_READ_OP        1
 #define MCPR_IMC_COMMAND_WRITE_OP       2
 
@@ -7659,6 +7660,28 @@ static int bnx2x_8726_read_sfp_module_eeprom(struct bnx2x_phy *phy,
         return -EINVAL;
 }
 
+static void bnx2x_warpcore_power_module(struct link_params *params,
+                                        struct bnx2x_phy *phy,
+                                        u8 power)
+{
+        u32 pin_cfg;
+        struct bnx2x *bp = params->bp;
+
+        pin_cfg = (REG_RD(bp, params->shmem_base +
+                          offsetof(struct shmem_region,
+                        dev_info.port_hw_config[params->port].e3_sfp_ctrl)) &
+                        PORT_HW_CFG_E3_PWR_DIS_MASK) >>
+                        PORT_HW_CFG_E3_PWR_DIS_SHIFT;
+
+        if (pin_cfg == PIN_CFG_NA)
+                return;
+        DP(NETIF_MSG_LINK, "Setting SFP+ module power to %d using pin cfg %d\n",
+                       power, pin_cfg);
+        /* Low ==> corresponding SFP+ module is powered
+         * high ==> the SFP+ module is powered down
+         */
+        bnx2x_set_cfg_pin(bp, pin_cfg, power ^ 1);
+}
 static int bnx2x_warpcore_read_sfp_module_eeprom(struct bnx2x_phy *phy,
                                                  struct link_params *params,
                                                  u16 addr, u8 byte_cnt,
@@ -7678,6 +7701,12 @@ static int bnx2x_warpcore_read_sfp_module_eeprom(struct bnx2x_phy *phy,
         /* 4 byte aligned address */
         addr32 = addr & (~0x3);
         do {
+                if (cnt == I2C_WA_PWR_ITER) {
+                        bnx2x_warpcore_power_module(params, phy, 0);
+                        /* Note that 100us are not enough here */
+                        usleep_range(1000,1000);
+                        bnx2x_warpcore_power_module(params, phy, 1);
+                }
                 rc = bnx2x_bsc_read(params, phy, 0xa0, addr32, 0, byte_cnt,
                                     data_array);
         } while ((rc != 0) && (++cnt < I2C_WA_RETRY_CNT));
@@ -8200,29 +8229,6 @@ static void bnx2x_set_sfp_module_fault_led(struct link_params *params,
                 bnx2x_set_e1e2_module_fault_led(params, gpio_mode);
 }
 
-static void bnx2x_warpcore_power_module(struct link_params *params,
-                                        struct bnx2x_phy *phy,
-                                        u8 power)
-{
-        u32 pin_cfg;
-        struct bnx2x *bp = params->bp;
-
-        pin_cfg = (REG_RD(bp, params->shmem_base +
-                          offsetof(struct shmem_region,
-                        dev_info.port_hw_config[params->port].e3_sfp_ctrl)) &
-                        PORT_HW_CFG_E3_PWR_DIS_MASK) >>
-                        PORT_HW_CFG_E3_PWR_DIS_SHIFT;
-
-        if (pin_cfg == PIN_CFG_NA)
-                return;
-        DP(NETIF_MSG_LINK, "Setting SFP+ module power to %d using pin cfg %d\n",
-                       power, pin_cfg);
-        /* Low ==> corresponding SFP+ module is powered
-         * high ==> the SFP+ module is powered down
-         */
-        bnx2x_set_cfg_pin(bp, pin_cfg, power ^ 1);
-}
-
 static void bnx2x_warpcore_hw_reset(struct bnx2x_phy *phy,
                                     struct link_params *params)
 {