ath5k: Wakeup fixes

* Don't put chip to full sleep because there are problems during
   wakeup. Instead hold MAC/Baseband on warm reset state via a new
   function ath5k_hw_on_hold.

 * Minor cleanups

Signed-off-by: Nick Kossifidis <mickflemm@gmail.com>
Tested-by: Ben Greear <greearb@candelatech.com>
Tested-by: Johannes Stezenbach <js@sig21.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

4 files changed, 140 insertions, 62 deletions

diff --git a/drivers/net/wireless/ath/ath5k/ath5k.h b/drivers/net/wireless/ath/ath5k/ath5k.h
index 91375113916b..1047a6cb1d92 100644
--- a/drivers/net/wireless/ath/ath5k/ath5k.h
+++ b/drivers/net/wireless/ath/ath5k/ath5k.h
@@ -1157,6 +1157,7 @@ extern void ath5k_unregister_leds(struct ath5k_softc *sc);
 
 /* Reset Functions */
 extern int ath5k_hw_nic_wakeup(struct ath5k_hw *ah, int flags, bool initial);
+extern int ath5k_hw_on_hold(struct ath5k_hw *ah);
 extern int ath5k_hw_reset(struct ath5k_hw *ah, enum nl80211_iftype op_mode, struct ieee80211_channel *channel, bool change_channel);
 /* Power management functions */
 extern int ath5k_hw_set_power(struct ath5k_hw *ah, enum ath5k_power_mode mode, bool set_chip, u16 sleep_duration);
diff --git a/drivers/net/wireless/ath/ath5k/attach.c b/drivers/net/wireless/ath/ath5k/attach.c
index 626306592cf8..238eeb7e166e 100644
--- a/drivers/net/wireless/ath/ath5k/attach.c
+++ b/drivers/net/wireless/ath/ath5k/attach.c
@@ -145,7 +145,7 @@ struct ath5k_hw *ath5k_hw_attach(struct ath5k_softc *sc, u8 mac_version)
                 goto err_free;
 
         /* Bring device out of sleep and reset it's units */
-        ret = ath5k_hw_nic_wakeup(ah, CHANNEL_B, true);
+        ret = ath5k_hw_nic_wakeup(ah, 0, true);
         if (ret)
                 goto err_free;
 
diff --git a/drivers/net/wireless/ath/ath5k/base.c b/drivers/net/wireless/ath/ath5k/base.c
index 5d5028538ac2..0370cba8356c 100644
--- a/drivers/net/wireless/ath/ath5k/base.c
+++ b/drivers/net/wireless/ath/ath5k/base.c
@@ -2446,27 +2446,29 @@ ath5k_stop_hw(struct ath5k_softc *sc)
         ret = ath5k_stop_locked(sc);
         if (ret == 0 && !test_bit(ATH_STAT_INVALID, sc->status)) {
                 /*
-                 * Set the chip in full sleep mode.  Note that we are
-                 * careful to do this only when bringing the interface
-                 * completely to a stop.  When the chip is in this state
-                 * it must be carefully woken up or references to
-                 * registers in the PCI clock domain may freeze the bus
-                 * (and system).  This varies by chip and is mostly an
-                 * issue with newer parts that go to sleep more quickly.
-                 */
-                if (sc->ah->ah_mac_srev >= 0x78) {
-                        /*
-                         * XXX
-                         * don't put newer MAC revisions > 7.8 to sleep because
-                         * of the above mentioned problems
-                         */
-                        ATH5K_DBG(sc, ATH5K_DEBUG_RESET, "mac version > 7.8, "
-                                "not putting device to sleep\n");
-                } else {
-                        ATH5K_DBG(sc, ATH5K_DEBUG_RESET,
-                                "putting device to full sleep\n");
-                        ath5k_hw_set_power(sc->ah, AR5K_PM_FULL_SLEEP, true, 0);
-                }
+                 * Don't set the card in full sleep mode!
+                 *
+                 * a) When the device is in this state it must be carefully
+                 * woken up or references to registers in the PCI clock
+                 * domain may freeze the bus (and system).  This varies
+                 * by chip and is mostly an issue with newer parts
+                 * (madwifi sources mentioned srev >= 0x78) that go to
+                 * sleep more quickly.
+                 *
+                 * b) On older chips full sleep results a weird behaviour
+                 * during wakeup. I tested various cards with srev < 0x78
+                 * and they don't wake up after module reload, a second
+                 * module reload is needed to bring the card up again.
+                 *
+                 * Until we figure out what's going on don't enable
+                 * full chip reset on any chip (this is what Legacy HAL
+                 * and Sam's HAL do anyway). Instead Perform a full reset
+                 * on the device (same as initial state after attach) and
+                 * leave it idle (keep MAC/BB on warm reset) */
+                ret = ath5k_hw_on_hold(sc->ah);
+
+                ATH5K_DBG(sc, ATH5K_DEBUG_RESET,
+                                "putting device to sleep\n");
         }
         ath5k_txbuf_free(sc, sc->bbuf);
 
diff --git a/drivers/net/wireless/ath/ath5k/reset.c b/drivers/net/wireless/ath/ath5k/reset.c
index 86733fdb4774..34e13c700849 100644
--- a/drivers/net/wireless/ath/ath5k/reset.c
+++ b/drivers/net/wireless/ath/ath5k/reset.c
@@ -258,29 +258,35 @@ int ath5k_hw_set_power(struct ath5k_hw *ah, enum ath5k_power_mode mode,
                 if (!set_chip)
                         goto commit;
 
-                /* Preserve sleep duration */
                 data = ath5k_hw_reg_read(ah, AR5K_SLEEP_CTL);
+
+                /* If card is down we 'll get 0xffff... so we
+                 * need to clean this up before we write the register
+                 */
                 if (data & 0xffc00000)
                         data = 0;
                 else
-                        data = data & 0xfffcffff;
+                        /* Preserve sleep duration etc */
+                        data = data & ~AR5K_SLEEP_CTL_SLE;
 
-                ath5k_hw_reg_write(ah, data, AR5K_SLEEP_CTL);
+                ath5k_hw_reg_write(ah, data | AR5K_SLEEP_CTL_SLE_WAKE,
+                                                        AR5K_SLEEP_CTL);
                 udelay(15);
 
-                for (i = 50; i > 0; i--) {
+                for (i = 200; i > 0; i--) {
                         /* Check if the chip did wake up */
                         if ((ath5k_hw_reg_read(ah, AR5K_PCICFG) &
                                         AR5K_PCICFG_SPWR_DN) == 0)
                                 break;
 
                         /* Wait a bit and retry */
-                        udelay(200);
-                        ath5k_hw_reg_write(ah, data, AR5K_SLEEP_CTL);
+                        udelay(50);
+                        ath5k_hw_reg_write(ah, data | AR5K_SLEEP_CTL_SLE_WAKE,
+                                                        AR5K_SLEEP_CTL);
                 }
 
                 /* Fail if the chip didn't wake up */
-                if (i <= 0)
+                if (i == 0)
                         return -EIO;
 
                 break;
@@ -296,6 +302,64 @@ commit:
 }
 
 /*
+ * Put device on hold
+ *
+ * Put MAC and Baseband on warm reset and
+ * keep that state (don't clean sleep control
+ * register). After this MAC and Baseband are
+ * disabled and a full reset is needed to come
+ * back. This way we save as much power as possible
+ * without puting the card on full sleep.
+ */
+int ath5k_hw_on_hold(struct ath5k_hw *ah)
+{
+        struct pci_dev *pdev = ah->ah_sc->pdev;
+        u32 bus_flags;
+        int ret;
+
+        /* Make sure device is awake */
+        ret = ath5k_hw_set_power(ah, AR5K_PM_AWAKE, true, 0);
+        if (ret) {
+                ATH5K_ERR(ah->ah_sc, "failed to wakeup the MAC Chip\n");
+                return ret;
+        }
+
+        /*
+         * Put chipset on warm reset...
+         *
+         * Note: puting PCI core on warm reset on PCI-E cards
+         * results card to hang and always return 0xffff... so
+         * we ingore that flag for PCI-E cards. On PCI cards
+         * this flag gets cleared after 64 PCI clocks.
+         */
+        bus_flags = (pdev->is_pcie) ? 0 : AR5K_RESET_CTL_PCI;
+
+        if (ah->ah_version == AR5K_AR5210) {
+                ret = ath5k_hw_nic_reset(ah, AR5K_RESET_CTL_PCU |
+                        AR5K_RESET_CTL_MAC | AR5K_RESET_CTL_DMA |
+                        AR5K_RESET_CTL_PHY | AR5K_RESET_CTL_PCI);
+                        mdelay(2);
+        } else {
+                ret = ath5k_hw_nic_reset(ah, AR5K_RESET_CTL_PCU |
+                        AR5K_RESET_CTL_BASEBAND | bus_flags);
+        }
+
+        if (ret) {
+                ATH5K_ERR(ah->ah_sc, "failed to put device on warm reset\n");
+                return -EIO;
+        }
+
+        /* ...wakeup again!*/
+        ret = ath5k_hw_set_power(ah, AR5K_PM_AWAKE, true, 0);
+        if (ret) {
+                ATH5K_ERR(ah->ah_sc, "failed to put device on hold\n");
+                return ret;
+        }
+
+        return ret;
+}
+
+/*
  * Bring up MAC + PHY Chips and program PLL
  * TODO: Half/Quarter rate support
  */
@@ -318,6 +382,50 @@ int ath5k_hw_nic_wakeup(struct ath5k_hw *ah, int flags, bool initial)
                 return ret;
         }
 
+        /*
+         * Put chipset on warm reset...
+         *
+         * Note: puting PCI core on warm reset on PCI-E cards
+         * results card to hang and always return 0xffff... so
+         * we ingore that flag for PCI-E cards. On PCI cards
+         * this flag gets cleared after 64 PCI clocks.
+         */
+        bus_flags = (pdev->is_pcie) ? 0 : AR5K_RESET_CTL_PCI;
+
+        if (ah->ah_version == AR5K_AR5210) {
+                ret = ath5k_hw_nic_reset(ah, AR5K_RESET_CTL_PCU |
+                        AR5K_RESET_CTL_MAC | AR5K_RESET_CTL_DMA |
+                        AR5K_RESET_CTL_PHY | AR5K_RESET_CTL_PCI);
+                        mdelay(2);
+        } else {
+                ret = ath5k_hw_nic_reset(ah, AR5K_RESET_CTL_PCU |
+                        AR5K_RESET_CTL_BASEBAND | bus_flags);
+        }
+
+        if (ret) {
+                ATH5K_ERR(ah->ah_sc, "failed to reset the MAC Chip\n");
+                return -EIO;
+        }
+
+        /* ...wakeup again!...*/
+        ret = ath5k_hw_set_power(ah, AR5K_PM_AWAKE, true, 0);
+        if (ret) {
+                ATH5K_ERR(ah->ah_sc, "failed to resume the MAC Chip\n");
+                return ret;
+        }
+
+        /* ...clear reset control register and pull device out of
+         * warm reset */
+        if (ath5k_hw_nic_reset(ah, 0)) {
+                ATH5K_ERR(ah->ah_sc, "failed to warm reset the MAC Chip\n");
+                return -EIO;
+        }
+
+        /* On initialization skip PLL programming since we don't have
+         * a channel / mode set yet */
+        if (initial)
+                return 0;
+
         if (ah->ah_version != AR5K_AR5210) {
                 /*
                  * Get channel mode flags
@@ -383,39 +491,6 @@ int ath5k_hw_nic_wakeup(struct ath5k_hw *ah, int flags, bool initial)
                                         AR5K_PHY_TURBO);
         }
 
-        /* reseting PCI on PCI-E cards results card to hang
-         * and always return 0xffff... so we ingore that flag
-         * for PCI-E cards */
-        bus_flags = (pdev->is_pcie) ? 0 : AR5K_RESET_CTL_PCI;
-
-        /* Reset chipset */
-        if (ah->ah_version == AR5K_AR5210) {
-                ret = ath5k_hw_nic_reset(ah, AR5K_RESET_CTL_PCU |
-                        AR5K_RESET_CTL_MAC | AR5K_RESET_CTL_DMA |
-                        AR5K_RESET_CTL_PHY | AR5K_RESET_CTL_PCI);
-                        mdelay(2);
-        } else {
-                ret = ath5k_hw_nic_reset(ah, AR5K_RESET_CTL_PCU |
-                        AR5K_RESET_CTL_BASEBAND | bus_flags);
-        }
-        if (ret) {
-                ATH5K_ERR(ah->ah_sc, "failed to reset the MAC Chip\n");
-                return -EIO;
-        }
-
-        /* ...wakeup again!*/
-        ret = ath5k_hw_set_power(ah, AR5K_PM_AWAKE, true, 0);
-        if (ret) {
-                ATH5K_ERR(ah->ah_sc, "failed to resume the MAC Chip\n");
-                return ret;
-        }
-
-        /* ...final warm reset */
-        if (ath5k_hw_nic_reset(ah, 0)) {
-                ATH5K_ERR(ah->ah_sc, "failed to warm reset the MAC Chip\n");
-                return -EIO;
-        }
-
         if (ah->ah_version != AR5K_AR5210) {
 
                 /* ...update PLL if needed */