libertas: implement if_sdio runtime power management

The SDIO card is now fully powered down when the network interface is
brought down.

Signed-off-by: Daniel Drake <dsd@laptop.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 171 insertions, 106 deletions

diff --git a/drivers/net/wireless/libertas/if_sdio.c b/drivers/net/wireless/libertas/if_sdio.c
index 387786e1b394..c962e21762dc 100644
--- a/drivers/net/wireless/libertas/if_sdio.c
+++ b/drivers/net/wireless/libertas/if_sdio.c
@@ -39,6 +39,7 @@
 #include <linux/mmc/sdio_ids.h>
 #include <linux/mmc/sdio.h>
 #include <linux/mmc/host.h>
+#include <linux/pm_runtime.h>
 
 #include "host.h"
 #include "decl.h"
@@ -47,6 +48,8 @@
 #include "cmd.h"
 #include "if_sdio.h"
 
+static void if_sdio_interrupt(struct sdio_func *func);
+
 /* The if_sdio_remove() callback function is called when
  * user removes this module from kernel space or ejects
  * the card from the slot. The driver handles these 2 cases
@@ -757,6 +760,136 @@ out:
         return ret;
 }
 
+/********************************************************************/
+/* Power management                                                 */
+/********************************************************************/
+
+static int if_sdio_power_on(struct if_sdio_card *card)
+{
+        struct sdio_func *func = card->func;
+        struct lbs_private *priv = card->priv;
+        struct mmc_host *host = func->card->host;
+        int ret;
+
+        sdio_claim_host(func);
+
+        ret = sdio_enable_func(func);
+        if (ret)
+                goto release;
+
+        /* For 1-bit transfers to the 8686 model, we need to enable the
+         * interrupt flag in the CCCR register. Set the MMC_QUIRK_LENIENT_FN0
+         * bit to allow access to non-vendor registers. */
+        if ((card->model == MODEL_8686) &&
+            (host->caps & MMC_CAP_SDIO_IRQ) &&
+            (host->ios.bus_width == MMC_BUS_WIDTH_1)) {
+                u8 reg;
+
+                func->card->quirks |= MMC_QUIRK_LENIENT_FN0;
+                reg = sdio_f0_readb(func, SDIO_CCCR_IF, &ret);
+                if (ret)
+                        goto disable;
+
+                reg |= SDIO_BUS_ECSI;
+                sdio_f0_writeb(func, reg, SDIO_CCCR_IF, &ret);
+                if (ret)
+                        goto disable;
+        }
+
+        card->ioport = sdio_readb(func, IF_SDIO_IOPORT, &ret);
+        if (ret)
+                goto disable;
+
+        card->ioport |= sdio_readb(func, IF_SDIO_IOPORT + 1, &ret) << 8;
+        if (ret)
+                goto disable;
+
+        card->ioport |= sdio_readb(func, IF_SDIO_IOPORT + 2, &ret) << 16;
+        if (ret)
+                goto disable;
+
+        sdio_release_host(func);
+        ret = if_sdio_prog_firmware(card);
+        sdio_claim_host(func);
+        if (ret)
+                goto disable;
+
+        /*
+         * Get rx_unit if the chip is SD8688 or newer.
+         * SD8385 & SD8686 do not have rx_unit.
+         */
+        if ((card->model != MODEL_8385)
+                        && (card->model != MODEL_8686))
+                card->rx_unit = if_sdio_read_rx_unit(card);
+        else
+                card->rx_unit = 0;
+
+        /*
+         * Set up the interrupt handler late.
+         *
+         * If we set it up earlier, the (buggy) hardware generates a spurious
+         * interrupt, even before the interrupt has been enabled, with
+         * CCCR_INTx = 0.
+         *
+         * We register the interrupt handler late so that we can handle any
+         * spurious interrupts, and also to avoid generation of that known
+         * spurious interrupt in the first place.
+         */
+        ret = sdio_claim_irq(func, if_sdio_interrupt);
+        if (ret)
+                goto disable;
+
+        /*
+         * Enable interrupts now that everything is set up
+         */
+        sdio_writeb(func, 0x0f, IF_SDIO_H_INT_MASK, &ret);
+        if (ret)
+                goto release_irq;
+
+        sdio_release_host(func);
+
+        /*
+         * FUNC_INIT is required for SD8688 WLAN/BT multiple functions
+         */
+        if (card->model == MODEL_8688) {
+                struct cmd_header cmd;
+
+                memset(&cmd, 0, sizeof(cmd));
+
+                lbs_deb_sdio("send function INIT command\n");
+                if (__lbs_cmd(priv, CMD_FUNC_INIT, &cmd, sizeof(cmd),
+                                lbs_cmd_copyback, (unsigned long) &cmd))
+                        netdev_alert(priv->dev, "CMD_FUNC_INIT cmd failed\n");
+        }
+
+        priv->fw_ready = 1;
+
+        return 0;
+
+release_irq:
+        sdio_release_irq(func);
+disable:
+        sdio_disable_func(func);
+release:
+        sdio_release_host(func);
+        return ret;
+}
+
+static int if_sdio_power_off(struct if_sdio_card *card)
+{
+        struct sdio_func *func = card->func;
+        struct lbs_private *priv = card->priv;
+
+        priv->fw_ready = 0;
+
+        sdio_claim_host(func);
+        sdio_release_irq(func);
+        sdio_disable_func(func);
+        sdio_release_host(func);
+        return 0;
+}
+
+
 /*******************************************************************/
 /* Libertas callbacks                                              */
 /*******************************************************************/
@@ -923,6 +1056,32 @@ static void if_sdio_reset_card(struct lbs_private *priv)
         schedule_work(&card_reset_work);
 }
 
+static int if_sdio_power_save(struct lbs_private *priv)
+{
+        struct if_sdio_card *card = priv->card;
+        int ret;
+
+        flush_workqueue(card->workqueue);
+
+        ret = if_sdio_power_off(card);
+
+        /* Let runtime PM know the card is powered off */
+        pm_runtime_put_sync(&card->func->dev);
+
+        return ret;
+}
+
+static int if_sdio_power_restore(struct lbs_private *priv)
+{
+        struct if_sdio_card *card = priv->card;
+
+        /* Make sure the card will not be powered off by runtime PM */
+        pm_runtime_get_sync(&card->func->dev);
+
+        return if_sdio_power_on(card);
+}
+
+
 /*******************************************************************/
 /* SDIO callbacks                                                  */
 /*******************************************************************/
@@ -976,7 +1135,6 @@ static int if_sdio_probe(struct sdio_func *func,
         int ret, i;
         unsigned int model;
         struct if_sdio_packet *packet;
-        struct mmc_host *host = func->card->host;
 
         lbs_deb_enter(LBS_DEB_SDIO);
 
@@ -1033,45 +1191,6 @@ static int if_sdio_probe(struct sdio_func *func,
                 goto free;
         }
 
-        sdio_claim_host(func);
-
-        ret = sdio_enable_func(func);
-        if (ret)
-                goto release;
-
-        /* For 1-bit transfers to the 8686 model, we need to enable the
-         * interrupt flag in the CCCR register. Set the MMC_QUIRK_LENIENT_FN0
-         * bit to allow access to non-vendor registers. */
-        if ((card->model == MODEL_8686) &&
-            (host->caps & MMC_CAP_SDIO_IRQ) &&
-            (host->ios.bus_width == MMC_BUS_WIDTH_1)) {
-                u8 reg;
-
-                func->card->quirks |= MMC_QUIRK_LENIENT_FN0;
-                reg = sdio_f0_readb(func, SDIO_CCCR_IF, &ret);
-                if (ret)
-                        goto release_int;
-
-                reg |= SDIO_BUS_ECSI;
-                sdio_f0_writeb(func, reg, SDIO_CCCR_IF, &ret);
-                if (ret)
-                        goto release_int;
-        }
-
-        card->ioport = sdio_readb(func, IF_SDIO_IOPORT, &ret);
-        if (ret)
-                goto release_int;
-
-        card->ioport |= sdio_readb(func, IF_SDIO_IOPORT + 1, &ret) << 8;
-        if (ret)
-                goto release_int;
-
-        card->ioport |= sdio_readb(func, IF_SDIO_IOPORT + 2, &ret) << 16;
-        if (ret)
-                goto release_int;
-
-        sdio_release_host(func);
-
         sdio_set_drvdata(func, card);
 
         lbs_deb_sdio("class = 0x%X, vendor = 0x%X, "
@@ -1079,14 +1198,11 @@ static int if_sdio_probe(struct sdio_func *func,
                         func->class, func->vendor, func->device,
                         model, (unsigned)card->ioport);
 
-        ret = if_sdio_prog_firmware(card);
-        if (ret)
-                goto reclaim;
 
         priv = lbs_add_card(card, &func->dev);
         if (!priv) {
                 ret = -ENOMEM;
-                goto reclaim;
+                goto free;
         }
 
         card->priv = priv;
@@ -1097,62 +1213,21 @@ static int if_sdio_probe(struct sdio_func *func,
         priv->exit_deep_sleep = if_sdio_exit_deep_sleep;
         priv->reset_deep_sleep_wakeup = if_sdio_reset_deep_sleep_wakeup;
         priv->reset_card = if_sdio_reset_card;
+        priv->power_save = if_sdio_power_save;
+        priv->power_restore = if_sdio_power_restore;
 
-        sdio_claim_host(func);
-
-        /*
-         * Get rx_unit if the chip is SD8688 or newer.
-         * SD8385 & SD8686 do not have rx_unit.
-         */
-        if ((card->model != MODEL_8385)
-                        && (card->model != MODEL_8686))
-                card->rx_unit = if_sdio_read_rx_unit(card);
-        else
-                card->rx_unit = 0;
-
-        /*
-         * Set up the interrupt handler late.
-         *
-         * If we set it up earlier, the (buggy) hardware generates a spurious
-         * interrupt, even before the interrupt has been enabled, with
-         * CCCR_INTx = 0.
-         *
-         * We register the interrupt handler late so that we can handle any
-         * spurious interrupts, and also to avoid generation of that known
-         * spurious interrupt in the first place.
-         */
-        ret = sdio_claim_irq(func, if_sdio_interrupt);
-        if (ret)
-                goto disable;
-
-        /*
-         * Enable interrupts now that everything is set up
-         */
-        sdio_writeb(func, 0x0f, IF_SDIO_H_INT_MASK, &ret);
-        sdio_release_host(func);
+        ret = if_sdio_power_on(card);
         if (ret)
-                goto reclaim;
-
-        priv->fw_ready = 1;
-
-        /*
-         * FUNC_INIT is required for SD8688 WLAN/BT multiple functions
-         */
-        if (card->model == MODEL_8688) {
-                struct cmd_header cmd;
-
-                memset(&cmd, 0, sizeof(cmd));
-
-                lbs_deb_sdio("send function INIT command\n");
-                if (__lbs_cmd(priv, CMD_FUNC_INIT, &cmd, sizeof(cmd),
-                                lbs_cmd_copyback, (unsigned long) &cmd))
-                        netdev_alert(priv->dev, "CMD_FUNC_INIT cmd failed\n");
-        }
+                goto err_activate_card;
 
         ret = lbs_start_card(priv);
+        if_sdio_power_off(card);
         if (ret)
                 goto err_activate_card;
 
+        /* Tell PM core that we don't need the card to be powered now */
+        pm_runtime_put_noidle(&func->dev);
+
 out:
         lbs_deb_leave_args(LBS_DEB_SDIO, "ret %d", ret);
 
@@ -1161,14 +1236,6 @@ out:
 err_activate_card:
         flush_workqueue(card->workqueue);
         lbs_remove_card(priv);
-reclaim:
-        sdio_claim_host(func);
-release_int:
-        sdio_release_irq(func);
-disable:
-        sdio_disable_func(func);
-release:
-        sdio_release_host(func);
 free:
         destroy_workqueue(card->workqueue);
         while (card->packets) {
@@ -1195,6 +1262,9 @@ static void if_sdio_remove(struct sdio_func *func)
 
         card = sdio_get_drvdata(func);
 
+        /* Undo decrement done above in if_sdio_probe */
+        pm_runtime_get_noresume(&func->dev);
+
         if (user_rmmod && (card->model == MODEL_8688)) {
                 /*
                  * FUNC_SHUTDOWN is required for SD8688 WLAN/BT
@@ -1219,11 +1289,6 @@ static void if_sdio_remove(struct sdio_func *func)
         flush_workqueue(card->workqueue);
         destroy_workqueue(card->workqueue);
 
-        sdio_claim_host(func);
-        sdio_release_irq(func);
-        sdio_disable_func(func);
-        sdio_release_host(func);
-
         while (card->packets) {
                 packet = card->packets;
                 card->packets = card->packets->next;