From: Nikita Shubin <nikita.shubin@xxxxxxxxxxx> commit 00c33482bb6110bce8110daa351f9b3baf4df7dc upstream. Mismatch in probe platform_set_drvdata set's and method's that call dev_get_platdata will result in "Unable to handle kernel NULL pointer dereference", let's use according method for getting driver data after platform_set_drvdata. 8<--- cut here --- Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = (ptrval) [00000000] *pgd=00000000 Internal error: Oops: 5 [#1] ARM Modules linked in: CPU: 0 PID: 1 Comm: swapper Not tainted 5.9.10-00003-g723e101e0037-dirty #4 Hardware name: Technologic Systems TS-72xx SBC PC is at ep93xx_rtc_read_time+0xc/0x2c LR is at __rtc_read_time+0x4c/0x8c [...] [<c02b01c8>] (ep93xx_rtc_read_time) from [<c02ac38c>] (__rtc_read_time+0x4c/0x8c) [<c02ac38c>] (__rtc_read_time) from [<c02ac3f8>] (rtc_read_time+0x2c/0x4c) [<c02ac3f8>] (rtc_read_time) from [<c02acc54>] (__rtc_read_alarm+0x28/0x358) [<c02acc54>] (__rtc_read_alarm) from [<c02abd80>] (__rtc_register_device+0x124/0x2ec) [<c02abd80>] (__rtc_register_device) from [<c02b028c>] (ep93xx_rtc_probe+0xa4/0xac) [<c02b028c>] (ep93xx_rtc_probe) from [<c026424c>] (platform_drv_probe+0x24/0x5c) [<c026424c>] (platform_drv_probe) from [<c0262918>] (really_probe+0x218/0x374) [<c0262918>] (really_probe) from [<c0262da0>] (device_driver_attach+0x44/0x60) [<c0262da0>] (device_driver_attach) from [<c0262e70>] (__driver_attach+0xb4/0xc0) [<c0262e70>] (__driver_attach) from [<c0260d44>] (bus_for_each_dev+0x68/0xac) [<c0260d44>] (bus_for_each_dev) from [<c026223c>] (driver_attach+0x18/0x24) [<c026223c>] (driver_attach) from [<c0261dd8>] (bus_add_driver+0x150/0x1b4) [<c0261dd8>] (bus_add_driver) from [<c026342c>] (driver_register+0xb0/0xf4) [<c026342c>] (driver_register) from [<c0264210>] (__platform_driver_register+0x30/0x48) [<c0264210>] (__platform_driver_register) from [<c04cb9ac>] (ep93xx_rtc_driver_init+0x10/0x1c) [<c04cb9ac>] (ep93xx_rtc_driver_init) from [<c000973c>] (do_one_initcall+0x7c/0x1c0) [<c000973c>] (do_one_initcall) from [<c04b9ecc>] (kernel_init_freeable+0x168/0x1ac) [<c04b9ecc>] (kernel_init_freeable) from [<c03b2228>] (kernel_init+0x8/0xf4) [<c03b2228>] (kernel_init) from [<c00082c0>] (ret_from_fork+0x14/0x34) Exception stack(0xc441dfb0 to 0xc441dff8) dfa0: 00000000 00000000 00000000 00000000 dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 dfe0: 00000000 00000000 00000000 00000000 00000013 00000000 Code: e12fff1e e92d4010 e590303c e1a02001 (e5933000) ---[ end trace c914d6030eaa95c8 ]--- Fixes: b809d192eb98 ("rtc: ep93xx: stop setting platform_data") Signed-off-by: Nikita Shubin <nikita.shubin@xxxxxxxxxxx> Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Link: https://lore.kernel.org/r/20201201095507.10317-1-nikita.shubin@xxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/rtc/rtc-ep93xx.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/drivers/rtc/rtc-ep93xx.c +++ b/drivers/rtc/rtc-ep93xx.c @@ -33,7 +33,7 @@ struct ep93xx_rtc { static int ep93xx_rtc_get_swcomp(struct device *dev, unsigned short *preload, unsigned short *delete) { - struct ep93xx_rtc *ep93xx_rtc = dev_get_platdata(dev); + struct ep93xx_rtc *ep93xx_rtc = dev_get_drvdata(dev); unsigned long comp; comp = readl(ep93xx_rtc->mmio_base + EP93XX_RTC_SWCOMP); @@ -51,7 +51,7 @@ static int ep93xx_rtc_get_swcomp(struct static int ep93xx_rtc_read_time(struct device *dev, struct rtc_time *tm) { - struct ep93xx_rtc *ep93xx_rtc = dev_get_platdata(dev); + struct ep93xx_rtc *ep93xx_rtc = dev_get_drvdata(dev); unsigned long time; time = readl(ep93xx_rtc->mmio_base + EP93XX_RTC_DATA); @@ -62,7 +62,7 @@ static int ep93xx_rtc_read_time(struct d static int ep93xx_rtc_set_time(struct device *dev, struct rtc_time *tm) { - struct ep93xx_rtc *ep93xx_rtc = dev_get_platdata(dev); + struct ep93xx_rtc *ep93xx_rtc = dev_get_drvdata(dev); unsigned long secs = rtc_tm_to_time64(tm); writel(secs + 1, ep93xx_rtc->mmio_base + EP93XX_RTC_LOAD);