brcmfmac: handle SDIO card removal

When removing the card the driver still tries to access registers
in the device. This patch adds another state for the bus that
indicates the device is no longer reachable. This avoids errors
accessing it while cleaning up the driver.

Reviewed-by: Franky Lin <frankyl@broadcom.com>
Reviewed-by: Hante Meuleman <meuleman@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 50 insertions, 70 deletions

diff --git a/drivers/net/wireless/brcm80211/brcmfmac/dhd_sdio.c b/drivers/net/wireless/brcm80211/brcmfmac/dhd_sdio.c
index ef24a1bd24a7..3e991897d7ca 100644
--- a/drivers/net/wireless/brcm80211/brcmfmac/dhd_sdio.c
+++ b/drivers/net/wireless/brcm80211/brcmfmac/dhd_sdio.c
@@ -1082,10 +1082,6 @@ static void brcmf_sdio_rxfail(struct brcmf_sdio *bus, bool abort, bool rtx)
 
 	/* Clear partial in any case */
 	bus->cur_read.len = 0;
-
-	/* If we can't reach the device, signal failure */
-	if (err)
-		bus->sdiodev->bus_if->state = BRCMF_BUS_DOWN;
 }
 
 /* return total length of buffer chain */
@@ -1682,8 +1678,7 @@ static uint brcmf_sdio_readframes(struct brcmf_sdio *bus, uint maxframes)
 	bus->rxpending = true;
 
 	for (rd->seq_num = bus->rx_seq, rxleft = maxframes;
-	     !bus->rxskip && rxleft &&
-	     bus->sdiodev->bus_if->state != BRCMF_BUS_DOWN;
+	     !bus->rxskip && rxleft && brcmf_bus_ready(bus->sdiodev->bus_if);
 	     rd->seq_num++, rxleft--) {
 
 		/* Handle glomming separately */
@@ -2232,39 +2227,37 @@ static void brcmf_sdio_bus_stop(struct device *dev)
 		bus->watchdog_tsk = NULL;
 	}
 
-	sdio_claim_host(bus->sdiodev->func[1]);
-
-	/* Enable clock for device interrupts */
-	brcmf_sdio_bus_sleep(bus, false, false);
+	if (bus_if->state == BRCMF_BUS_DOWN) {
+		sdio_claim_host(sdiodev->func[1]);
+
+		/* Enable clock for device interrupts */
+		brcmf_sdio_bus_sleep(bus, false, false);
+
+		/* Disable and clear interrupts at the chip level also */
+		w_sdreg32(bus, 0, offsetof(struct sdpcmd_regs, hostintmask));
+		local_hostintmask = bus->hostintmask;
+		bus->hostintmask = 0;
+
+		/* Force backplane clocks to assure F2 interrupt propagates */
+		saveclk = brcmf_sdiod_regrb(sdiodev, SBSDIO_FUNC1_CHIPCLKCSR,
+					    &err);
+		if (!err)
+			brcmf_sdiod_regwb(sdiodev, SBSDIO_FUNC1_CHIPCLKCSR,
+					  (saveclk | SBSDIO_FORCE_HT), &err);
+		if (err)
+			brcmf_err("Failed to force clock for F2: err %d\n",
+				  err);
 
-	/* Disable and clear interrupts at the chip level also */
-	w_sdreg32(bus, 0, offsetof(struct sdpcmd_regs, hostintmask));
-	local_hostintmask = bus->hostintmask;
-	bus->hostintmask = 0;
+		/* Turn off the bus (F2), free any pending packets */
+		brcmf_dbg(INTR, "disable SDIO interrupts\n");
+		sdio_disable_func(sdiodev->func[SDIO_FUNC_2]);
 
-	/* Change our idea of bus state */
-	bus->sdiodev->bus_if->state = BRCMF_BUS_DOWN;
+		/* Clear any pending interrupts now that F2 is disabled */
+		w_sdreg32(bus, local_hostintmask,
+			  offsetof(struct sdpcmd_regs, intstatus));
 
-	/* Force clocks on backplane to be sure F2 interrupt propagates */
-	saveclk = brcmf_sdiod_regrb(bus->sdiodev,
-				    SBSDIO_FUNC1_CHIPCLKCSR, &err);
-	if (!err) {
-		brcmf_sdiod_regwb(bus->sdiodev, SBSDIO_FUNC1_CHIPCLKCSR,
-				  (saveclk | SBSDIO_FORCE_HT), &err);
+		sdio_release_host(sdiodev->func[1]);
 	}
-	if (err)
-		brcmf_err("Failed to force clock for F2: err %d\n", err);
-
-	/* Turn off the bus (F2), free any pending packets */
-	brcmf_dbg(INTR, "disable SDIO interrupts\n");
-	sdio_disable_func(bus->sdiodev->func[SDIO_FUNC_2]);
-
-	/* Clear any pending interrupts now that F2 is disabled */
-	w_sdreg32(bus, local_hostintmask,
-		  offsetof(struct sdpcmd_regs, intstatus));
-
-	sdio_release_host(bus->sdiodev->func[1]);
-
 	/* Clear the data packet queues */
 	brcmu_pktq_flush(&bus->txq, true, NULL, NULL);
 
@@ -2354,20 +2347,11 @@ static void brcmf_sdio_dpc(struct brcmf_sdio *bus)
 		/* Check for inconsistent device control */
 		devctl = brcmf_sdiod_regrb(bus->sdiodev,
 					   SBSDIO_DEVICE_CTL, &err);
-		if (err) {
-			brcmf_err("error reading DEVCTL: %d\n", err);
-			bus->sdiodev->bus_if->state = BRCMF_BUS_DOWN;
-		}
 #endif				/* DEBUG */
 
 		/* Read CSR, if clock on switch to AVAIL, else ignore */
 		clkctl = brcmf_sdiod_regrb(bus->sdiodev,
 					   SBSDIO_FUNC1_CHIPCLKCSR, &err);
-		if (err) {
-			brcmf_err("error reading CSR: %d\n",
-				  err);
-			bus->sdiodev->bus_if->state = BRCMF_BUS_DOWN;
-		}
 
 		brcmf_dbg(SDIO, "DPC: PENDING, devctl 0x%02x clkctl 0x%02x\n",
 			  devctl, clkctl);
@@ -2375,19 +2359,9 @@ static void brcmf_sdio_dpc(struct brcmf_sdio *bus)
 		if (SBSDIO_HTAV(clkctl)) {
 			devctl = brcmf_sdiod_regrb(bus->sdiodev,
 						   SBSDIO_DEVICE_CTL, &err);
-			if (err) {
-				brcmf_err("error reading DEVCTL: %d\n",
-					  err);
-				bus->sdiodev->bus_if->state = BRCMF_BUS_DOWN;
-			}
 			devctl &= ~SBSDIO_DEVCTL_CA_INT_ONLY;
 			brcmf_sdiod_regwb(bus->sdiodev, SBSDIO_DEVICE_CTL,
 					  devctl, &err);
-			if (err) {
-				brcmf_err("error writing DEVCTL: %d\n",
-					  err);
-				bus->sdiodev->bus_if->state = BRCMF_BUS_DOWN;
-			}
 			bus->clkstate = CLK_AVAIL;
 		}
 	}
@@ -2522,9 +2496,8 @@ static void brcmf_sdio_dpc(struct brcmf_sdio *bus)
 		txlimit -= framecnt;
 	}
 
-	if ((bus->sdiodev->bus_if->state == BRCMF_BUS_DOWN) || (err != 0)) {
+	if (!brcmf_bus_ready(bus->sdiodev->bus_if) || (err != 0)) {
 		brcmf_err("failed backplane access over SDIO, halting operation\n");
-		bus->sdiodev->bus_if->state = BRCMF_BUS_DOWN;
 		atomic_set(&bus->intstatus, 0);
 	} else if (atomic_read(&bus->intstatus) ||
 		   atomic_read(&bus->ipend) > 0 ||
@@ -3356,7 +3329,7 @@ static int brcmf_sdio_download_firmware(struct brcmf_sdio *bus)
 	}
 
 	/* Allow HT Clock now that the ARM is running. */
-	bus->sdiodev->bus_if->state = BRCMF_BUS_LOAD;
+	brcmf_bus_change_state(bus->sdiodev->bus_if, BRCMF_BUS_LOAD);
 	bcmerror = 0;
 
 err:
@@ -3633,7 +3606,7 @@ void brcmf_sdio_isr(struct brcmf_sdio *bus)
 		return;
 	}
 
-	if (bus->sdiodev->bus_if->state == BRCMF_BUS_DOWN) {
+	if (!brcmf_bus_ready(bus->sdiodev->bus_if)) {
 		brcmf_err("bus is down. we have nothing to do\n");
 		return;
 	}
@@ -3644,7 +3617,6 @@ void brcmf_sdio_isr(struct brcmf_sdio *bus)
 	else
 		if (brcmf_sdio_intr_rstatus(bus)) {
 			brcmf_err("failed backplane access\n");
-			bus->sdiodev->bus_if->state = BRCMF_BUS_DOWN;
 		}
 
 	/* Disable additional interrupts (is this needed now)? */
@@ -3781,6 +3753,11 @@ brcmf_sdio_probe_attach(struct brcmf_sdio *bus)
 		goto fail;
 	}
 
+	/* SDIO register access works so moving
+	 * state from UNKNOWN to DOWN.
+	 */
+	brcmf_bus_change_state(bus->sdiodev->bus_if, BRCMF_BUS_DOWN);
+
 	if (brcmf_sdio_chip_attach(bus->sdiodev, &bus->ci)) {
 		brcmf_err("brcmf_sdio_chip_attach failed!\n");
 		goto fail;
@@ -4004,7 +3981,6 @@ struct brcmf_sdio *brcmf_sdio_probe(struct brcmf_sdio_dev *sdiodev)
 	/* Disable F2 to clear any intermediate frame state on the dongle */
 	sdio_disable_func(bus->sdiodev->func[SDIO_FUNC_2]);
 
-	bus->sdiodev->bus_if->state = BRCMF_BUS_DOWN;
 	bus->rxflow = false;
 
 	/* Done with backplane-dependent accesses, can drop clock... */
@@ -4060,16 +4036,20 @@ void brcmf_sdio_remove(struct brcmf_sdio *bus)
 		}
 
 		if (bus->ci) {
-			sdio_claim_host(bus->sdiodev->func[1]);
-			brcmf_sdio_clkctl(bus, CLK_AVAIL, false);
-			/* Leave the device in state where it is 'quiet'. This
-			 * is done by putting it in download_state which
-			 * essentially resets all necessary cores
-			 */
-			msleep(20);
-			brcmf_sdio_chip_enter_download(bus->sdiodev, bus->ci);
-			brcmf_sdio_clkctl(bus, CLK_NONE, false);
-			sdio_release_host(bus->sdiodev->func[1]);
+			if (bus->sdiodev->bus_if->state == BRCMF_BUS_DOWN) {
+				sdio_claim_host(bus->sdiodev->func[1]);
+				brcmf_sdio_clkctl(bus, CLK_AVAIL, false);
+				/* Leave the device in state where it is
+				 * 'quiet'. This is done by putting it in
+				 * download_state which essentially resets
+				 * all necessary cores.
+				 */
+				msleep(20);
+				brcmf_sdio_chip_enter_download(bus->sdiodev,
+							       bus->ci);
+				brcmf_sdio_clkctl(bus, CLK_NONE, false);
+				sdio_release_host(bus->sdiodev->func[1]);
+			}
 			brcmf_sdio_chip_detach(&bus->ci);
 		}