From 467a44b0372d8268ce5bd90e58bde7db51c1d476 Mon Sep 17 00:00:00 2001 From: Alexandre Belloni Date: Sat, 3 May 2014 16:57:00 +0100 Subject: [PATCH] iio: adc: at91_adc: Repair broken platform_data support Trying to use the at91_adc driver while not using device tree is ending up in a kernel crash: Unable to handle kernel NULL pointer dereference at virtual address 00000004 [...] [] (at91_adc_probe) from [] (platform_drv_probe+0x18/0x48) [] (platform_drv_probe) from [] (driver_probe_device+0x100/0x218) [] (driver_probe_device) from [] (__driver_attach+0x8c/0x90) [] (__driver_attach) from [] (bus_for_each_dev+0x58/0x88) [] (bus_for_each_dev) from [] (bus_add_driver+0xd4/0x1d4) [] (bus_add_driver) from [] (driver_register+0x78/0xf4) [] (driver_register) from [] (do_one_initcall+0xe8/0x14c) [] (do_one_initcall) from [] (kernel_init_freeable+0xec/0x1b4) [] (kernel_init_freeable) from [] (kernel_init+0x8/0xe4) [] (kernel_init) from [] (ret_from_fork+0x14/0x24) This is because the at91_adc_caps structure is mandatory but is not filled when using platform_data. Correct that by using an id_table. It ensues that the driver will not match "at91_adc" anymore but it was crashing anyway. Fixes: c46016665fff (iio: at91: ADC start-up time calculation changed since at91sam9x5) Cc: stable@vger.kernel.org # v3.13+ Signed-off-by: Alexandre Belloni Tested-by: Josh Wu Acked-by: Josh Wu Signed-off-by: Jonathan Cameron --- drivers/iio/adc/at91_adc.c | 26 ++++++++++++++++++++++---- 1 file changed, 22 insertions(+), 4 deletions(-) diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c index 5b1aa027c034..bbba014c9939 100644 --- a/drivers/iio/adc/at91_adc.c +++ b/drivers/iio/adc/at91_adc.c @@ -765,14 +765,17 @@ static int at91_adc_probe_pdata(struct at91_adc_state *st, if (!pdata) return -EINVAL; + st->caps = (struct at91_adc_caps *) + platform_get_device_id(pdev)->driver_data; + st->use_external = pdata->use_external_triggers; st->vref_mv = pdata->vref; st->channels_mask = pdata->channels_used; - st->num_channels = pdata->num_channels; + st->num_channels = st->caps->num_channels; st->startup_time = pdata->startup_time; st->trigger_number = pdata->trigger_number; st->trigger_list = pdata->trigger_list; - st->registers = pdata->registers; + st->registers = &st->caps->registers; return 0; } @@ -1101,7 +1104,6 @@ static int at91_adc_remove(struct platform_device *pdev) return 0; } -#ifdef CONFIG_OF static struct at91_adc_caps at91sam9260_caps = { .calc_startup_ticks = calc_startup_ticks_9260, .num_channels = 4, @@ -1154,11 +1156,27 @@ static const struct of_device_id at91_adc_dt_ids[] = { {}, }; MODULE_DEVICE_TABLE(of, at91_adc_dt_ids); -#endif + +static const struct platform_device_id at91_adc_ids[] = { + { + .name = "at91sam9260-adc", + .driver_data = (unsigned long)&at91sam9260_caps, + }, { + .name = "at91sam9g45-adc", + .driver_data = (unsigned long)&at91sam9g45_caps, + }, { + .name = "at91sam9x5-adc", + .driver_data = (unsigned long)&at91sam9x5_caps, + }, { + /* terminator */ + } +}; +MODULE_DEVICE_TABLE(platform, at91_adc_ids); static struct platform_driver at91_adc_driver = { .probe = at91_adc_probe, .remove = at91_adc_remove, + .id_table = at91_adc_ids, .driver = { .name = DRIVER_NAME, .of_match_table = of_match_ptr(at91_adc_dt_ids), -- 2.39.5