Return-path: Received: from softlayer.compulab.co.il ([50.23.254.55]:46105 "EHLO compulab.co.il" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755584AbbLWIfx (ORCPT ); Wed, 23 Dec 2015 03:35:53 -0500 From: Uri Mashiach To: Kalle Valo , Rob Herring , Tony Lindgren Cc: Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , bcousson@baylibre.com, Igor Grinberg , Eliad Peller , devicetree@vger.kernel.org, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-wireless@vger.kernel.org, Uri Mashiach Subject: [PATCH 1/3] wlcore/wl12xx: spi: fix NULL pointer dereference (Oops) Date: Wed, 23 Dec 2015 10:35:42 +0200 Message-Id: <1450859744-9948-2-git-send-email-uri.mashiach@compulab.co.il> (sfid-20151223_093620_660353_B339E74C) In-Reply-To: <1450859744-9948-1-git-send-email-uri.mashiach@compulab.co.il> References: <1450859744-9948-1-git-send-email-uri.mashiach@compulab.co.il> Sender: linux-wireless-owner@vger.kernel.org List-ID: The power function uses a consumer regulator access to update the WiFi enable GPIO value. Fix the below Oops when trying to modprobe wlcore_spi. The oops occurs because the wl1271_power_{off,on}() function doesn't check the power() function pointer. [ 23.401447] Unable to handle kernel NULL pointer dereference at virtual address 00000000 [ 23.409954] pgd = c0004000 [ 23.412922] [00000000] *pgd=00000000 [ 23.416693] Internal error: Oops: 80000007 [#1] SMP ARM [ 23.422168] Modules linked in: wl12xx wlcore mac80211 cfg80211 musb_dsps musb_hdrc usbcore usb_common snd_soc_simple_card evdev joydev omap_rng wlcore_spi snd_soc_tlv320aic23_i2c rng_core snd_soc_tlv320aic23 c_can_platform c_can can_dev snd_soc_davinci_mcasp snd_soc_edma snd_soc_omap omap_wdt musb_am335x cpufreq_dt thermal_sys hwmon [ 23.453253] CPU: 0 PID: 36 Comm: kworker/0:2 Not tainted 4.2.0-00002-g951efee-dirty #233 [ 23.461720] Hardware name: Generic AM33XX (Flattened Device Tree) [ 23.468123] Workqueue: events request_firmware_work_func [ 23.473690] task: de32efc0 ti: de4ee000 task.ti: de4ee000 [ 23.479341] PC is at 0x0 [ 23.482112] LR is at wl12xx_set_power_on+0x28/0x124 [wlcore] [ 23.488074] pc : [<00000000>] lr : [] psr: 60000013 [ 23.488074] sp : de4efe50 ip : 00000002 fp : 00000000 [ 23.500162] r10: de7cdd00 r9 : dc848800 r8 : bf27af00 [ 23.505663] r7 : bf27a1a8 r6 : dcbd8a80 r5 : dce0e2e0 r4 : dce0d2e0 [ 23.512536] r3 : 00000000 r2 : 00000000 r1 : 00000001 r0 : dc848810 [ 23.519412] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel [ 23.527109] Control: 10c5387d Table: 9cb78019 DAC: 00000015 [ 23.533160] Process kworker/0:2 (pid: 36, stack limit = 0xde4ee218) [ 23.539760] Stack: (0xde4efe50 to 0xde4f0000) [...] [ 23.665030] [] (wl12xx_set_power_on [wlcore]) from [] (wlcore_nvs_cb+0x118/0xa4c [wlcore]) [ 23.675604] [] (wlcore_nvs_cb [wlcore]) from [] (request_firmware_work_func+0x30/0x58) [ 23.685784] [] (request_firmware_work_func) from [] (process_one_work+0x1b4/0x4b4) [ 23.695591] [] (process_one_work) from [] (worker_thread+0x3c/0x4a4) [ 23.704124] [] (worker_thread) from [] (kthread+0xd4/0xf0) [ 23.711747] [] (kthread) from [] (ret_from_fork+0x14/0x3c) [ 23.719357] Code: bad PC value [ 23.722760] ---[ end trace 981be8510db9b3a9 ]--- Fix this by adding a power() function implementation. Signed-off-by: Uri Mashiach Acked-by: Igor Grinberg --- drivers/net/wireless/ti/wlcore/spi.c | 37 ++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) diff --git a/drivers/net/wireless/ti/wlcore/spi.c b/drivers/net/wireless/ti/wlcore/spi.c index 44f059f..d3a4bcb 100644 --- a/drivers/net/wireless/ti/wlcore/spi.c +++ b/drivers/net/wireless/ti/wlcore/spi.c @@ -30,6 +30,7 @@ #include #include #include +#include #include "wlcore.h" #include "wl12xx_80211.h" @@ -81,6 +82,7 @@ struct wl12xx_spi_glue { struct device *dev; struct platform_device *core; + struct regulator *reg; /* Power regulator */ }; static void wl12xx_spi_reset(struct device *child) @@ -318,11 +320,40 @@ static int __must_check wl12xx_spi_raw_write(struct device *child, int addr, return 0; } +/** + * wl12xx_spi_set_power - power on/off the wl12xx unit + * @child: wl12xx device handle. + * @enable: true/false to power on/off the unit. + * + * use the WiFi enable regulator to enable/disable the WiFi unit. + */ +static int wl12xx_spi_set_power(struct device *child, bool enable) +{ + int ret = 0; + struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent); + + WARN_ON(!glue->reg); + + /* Update regulator state */ + if (enable) { + ret = regulator_enable(glue->reg); + if (ret) + dev_err(child, "Power enable failure\n"); + } else { + ret = regulator_disable(glue->reg); + if (ret) + dev_err(child, "Power disable failure\n"); + } + + return ret; +} + static struct wl1271_if_operations spi_ops = { .read = wl12xx_spi_raw_read, .write = wl12xx_spi_raw_write, .reset = wl12xx_spi_reset, .init = wl12xx_spi_init, + .power = wl12xx_spi_set_power, .set_block_size = NULL, }; @@ -353,6 +384,12 @@ static int wl1271_probe(struct spi_device *spi) * comes from the board-peripherals file */ spi->bits_per_word = 32; + glue->reg = devm_regulator_get(&spi->dev, "vwlan"); + if (IS_ERR(glue->reg)) { + dev_err(glue->dev, "can't get regulator\n"); + return PTR_ERR(glue->reg); + } + ret = spi_setup(spi); if (ret < 0) { dev_err(glue->dev, "spi_setup failed\n"); -- 2.5.0