kernel/linux.git/drivers/nvmem/core.c, branch v5.4.113

nvmem: core: skip child nodes not matching binding

2021-03-04T09:26:37+00:00

[ Upstream commit 0445efacec75b85c2a3c176957ee050ba9be53f0 ] The nvmem cell binding applies to all eeprom child nodes matching "^.*@[0-9a-f]+$" without taking a compatible into account. Linux drivers, like at24, are even more extensive and assume _all_ at24 eeprom child nodes to be nvmem cells since e888d445ac33 ("nvmem: resolve cells from DT at registration time"). Since df5f3b6f5357 ("dt-bindings: nvmem: stm32: new property for data access"), the additionalProperties: True means it's Ok to have other properties as long as they don't match "^.*@[0-9a-f]+$". The barebox bootloader extends the MTD partitions binding to EEPROM and can fix up following device tree node: &eeprom { partitions { compatible = "fixed-partitions"; }; }; This is allowed binding-wise, but drivers using nvmem_register() like at24 will fail to parse because the function expects all child nodes to have a reg property present. This results in the whole EEPROM driver probe failing despite the device tree being correct. Fix this by skipping nodes lacking a reg property instead of returning an error. This effectively makes the drivers adhere to the binding because all nodes with a unit address must have a reg property and vice versa. Fixes: e888d445ac33 ("nvmem: resolve cells from DT at registration time"). Signed-off-by: Ahmad Fatoum Signed-off-by: Srinivas Kandagatla Link: https://lore.kernel.org/r/20210129171430.11328-6-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

nvmem: core: Fix a resource leak on error in nvmem_add_cells_from_of()

2021-03-04T09:26:37+00:00

[ Upstream commit 72e008ce307fa2f35f6783997378b32e83122839 ] This doesn't call of_node_put() on the error path so it leads to a memory leak. Fixes: 0749aa25af82 ("nvmem: core: fix regression in of_nvmem_cell_get()") Signed-off-by: Dan Carpenter Signed-off-by: Srinivas Kandagatla Link: https://lore.kernel.org/r/20210129171430.11328-2-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

nvmem: core: fix possibly memleak when use nvmem_cell_info_to_nvmem_cell()

2020-10-29T08:57:42+00:00

[ Upstream commit fc9eec4d643597cf4cb2fef17d48110e677610da ] Fix missing 'kfree_const(cell->name)' when call to nvmem_cell_info_to_nvmem_cell() in several places: * after nvmem_cell_info_to_nvmem_cell() failed during nvmem_add_cells() * during nvmem_device_cell_{read,write} when cell->name is kstrdup'ed() without calling kfree_const() at the end, but really there is no reason to do that 'dup, because the cell instance is allocated on the stack for some short period to be read/write without exposing it to the caller. So the new nvmem_cell_info_to_nvmem_cell_nodup() helper is introduced which is used to convert cell_info -> cell without name duplication as a lighweight version of nvmem_cell_info_to_nvmem_cell(). Fixes: e2a5402ec7c6 ("nvmem: Add nvmem_device based consumer apis.") Reviewed-by: Srinivas Kandagatla Acked-by: Srinivas Kandagatla Signed-off-by: Vadym Kochan Link: https://lore.kernel.org/r/20200923204456.14032-1-vadym.kochan@plvision.eu Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

nvmem: core: fix memory abort in cleanup path

2020-02-11T12:35:21+00:00

commit 16bb7abc4a6b9defffa294e4dc28383e62a1dbcf upstream. nvmem_cell_info_to_nvmem_cell implementation has static allocation of name. nvmem_add_cells_from_of() call may return error and kfree name results in memory abort. Use kstrdup_const() and kfree_const calls for name alloc and free. Unable to handle kernel paging request at virtual address ffffffffffe44888 Mem abort info: ESR = 0x96000006 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000006 CM = 0, WnR = 0 swapper pgtable: 64k pages, 48-bit VAs, pgdp=00000000815d0000 [ffffffffffe44888] pgd=0000000081d30803, pud=0000000081d30803, pmd=0000000000000000 Internal error: Oops: 96000006 [#1] PREEMPT SMP Modules linked in: CPU: 2 PID: 43 Comm: kworker/2:1 Tainted Hardware name: quill (DT) Workqueue: events deferred_probe_work_func pstate: a0000005 (NzCv daif -PAN -UAO) pc : kfree+0x38/0x278 lr : nvmem_cell_drop+0x68/0x80 sp : ffff80001284f9d0 x29: ffff80001284f9d0 x28: ffff0001f677e830 x27: ffff800011b0b000 x26: ffff0001c36e1008 x25: ffff8000112ad000 x24: ffff8000112c9000 x23: ffffffffffffffea x22: ffff800010adc7f0 x21: ffffffffffe44880 x20: ffff800011b0b068 x19: ffff80001122d380 x18: ffffffffffffffff x17: 00000000d5cb4756 x16: 0000000070b193b8 x15: ffff8000119538c8 x14: 0720072007200720 x13: 07200720076e0772 x12: 07750762072d0765 x11: 0773077507660765 x10: 072f073007300730 x9 : 0730073207380733 x8 : 0000000000000151 x7 : 07660765072f0720 x6 : ffff0001c00e0f00 x5 : 0000000000000000 x4 : ffff0001c0b43800 x3 : ffff800011b0b068 x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffffffdfffe00000 Call trace: kfree+0x38/0x278 nvmem_cell_drop+0x68/0x80 nvmem_device_remove_all_cells+0x2c/0x50 nvmem_register.part.9+0x520/0x628 devm_nvmem_register+0x48/0xa0 tegra_fuse_probe+0x140/0x1f0 platform_drv_probe+0x50/0xa0 really_probe+0x108/0x348 driver_probe_device+0x58/0x100 __device_attach_driver+0x90/0xb0 bus_for_each_drv+0x64/0xc8 __device_attach+0xd8/0x138 device_initial_probe+0x10/0x18 bus_probe_device+0x90/0x98 deferred_probe_work_func+0x74/0xb0 process_one_work+0x1e0/0x358 worker_thread+0x208/0x488 kthread+0x118/0x120 ret_from_fork+0x10/0x18 Code: d350feb5 f2dffbe0 aa1e03f6 8b151815 (f94006a0) ---[ end trace 49b1303c6b83198e ]--- Fixes: badcdff107cbf ("nvmem: Convert to using %pOFn instead of device_node.name") Signed-off-by: Bitan Biswas Cc: stable Signed-off-by: Srinivas Kandagatla Link: https://lore.kernel.org/r/20200109104017.6249-5-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman

drivers: Introduce device lookup variants by of_node

2019-07-30T11:07:41+00:00

Introduce wrappers for {bus/driver/class}_find_device() to locate devices by its of_node. Cc: Maarten Lankhorst Cc: Maxime Ripard Cc: dri-devel@lists.freedesktop.org Cc: David Airlie Cc: Daniel Vetter Cc: devicetree@vger.kernel.org Cc: Florian Fainelli Cc: Frank Rowand Cc: Heiko Stuebner Cc: Liam Girdwood Cc: linux-i2c@vger.kernel.org Cc: linux-rockchip@lists.infradead.org Cc: linux-spi@vger.kernel.org Cc: Mathieu Poirier Cc: Rob Herring Cc: Srinivas Kandagatla Cc: Takashi Iwai Cc: Alan Tull Cc: linux-fpga@vger.kernel.org Cc: Peter Rosin Cc: Florian Fainelli Cc: Heiner Kallweit Cc: "David S. Miller" Cc: Andrew Lunn Cc: Liam Girdwood Cc: "Rafael J. Wysocki" Cc: Thor Thayer Cc: Jiri Slaby Cc: Andrew Lunn Cc: Peter Rosin Signed-off-by: Suzuki K Poulose Acked-by: Lee Jones Acked-by: Wolfram Sang # I2C part Acked-by: Moritz Fischer # For FPGA part Acked-by: Mark Brown Link: https://lore.kernel.org/r/20190723221838.12024-3-suzuki.poulose@arm.com Signed-off-by: Greg Kroah-Hartman

bus_find_device: Unify the match callback with class_find_device

2019-06-24T03:22:31+00:00

There is an arbitrary difference between the prototypes of bus_find_device() and class_find_device() preventing their callers from passing the same pair of data and match() arguments to both of them, which is the const qualifier used in the prototype of class_find_device(). If that qualifier is also used in the bus_find_device() prototype, it will be possible to pass the same match() callback function to both bus_find_device() and class_find_device(), which will allow some optimizations to be made in order to avoid code duplication going forward. Also with that, constify the "data" parameter as it is passed as a const to the match function. For this reason, change the prototype of bus_find_device() to match the prototype of class_find_device() and adjust its callers to use the const qualifier in accordance with the new prototype of it. Cc: Alexander Shishkin Cc: Andrew Lunn Cc: Andreas Noever Cc: Arnd Bergmann Cc: Bjorn Helgaas Cc: Corey Minyard Cc: Christian Borntraeger Cc: David Kershner Cc: "David S. Miller" Cc: David Airlie Cc: Felipe Balbi Cc: Frank Rowand Cc: Grygorii Strashko Cc: Harald Freudenberger Cc: Hartmut Knaack Cc: Heiko Stuebner Cc: Jason Gunthorpe Cc: Jonathan Cameron Cc: "James E.J. Bottomley" Cc: Len Brown Cc: Mark Brown Cc: Michael Ellerman Cc: Michael Jamet Cc: "Martin K. Petersen" Cc: Peter Oberparleiter Cc: Sebastian Ott Cc: Srinivas Kandagatla Cc: Yehezkel Bernat Cc: rafael@kernel.org Acked-by: Corey Minyard Acked-by: David Kershner Acked-by: Mark Brown Acked-by: Rafael J. Wysocki Acked-by: Srinivas Kandagatla Acked-by: Wolfram Sang # for the I2C parts Acked-by: Rob Herring Signed-off-by: Suzuki K Poulose Signed-off-by: Greg Kroah-Hartman

nvmem: core: add NVMEM_SYSFS Kconfig

2019-04-25T17:44:33+00:00

Many nvmem providers are not very keen on having default sysfs nvmem entry, as most of the usecases for them are inside kernel itself. And in some cases read/writes to some areas in nvmem are restricted and trapped at secure monitor level, so accessing them from userspace would result in board reboots. This patch adds new NVMEM_SYSFS Kconfig to make binary sysfs entry an optional one. This provision will give more flexibility to users. This patch also moves existing sysfs code to a new file so that its not compiled in when its not really required. Signed-off-by: Srinivas Kandagatla Reviewed-by: Mika Westerberg Reviewed-by: Gaurav Kohli Tested-by: Gaurav Kohli Signed-off-by: Greg Kroah-Hartman

nvmem: core: fix read buffer in place

2019-04-25T17:43:12+00:00

When the bit_offset in the cell is zero, the pointer to the msb will not be properly initialized (ie, will still be pointing to the first byte in the buffer). This being the case, if there are bits to clear in the msb, those will be left untouched while the mask will incorrectly clear bit positions on the first byte. This commit also makes sure that any byte unused in the cell is cleared. Signed-off-by: Jorge Ramirez-Ortiz Signed-off-by: Srinivas Kandagatla Signed-off-by: Greg Kroah-Hartman

nvmem: core: add nvmem_cell_read_u16

2019-04-25T17:43:12+00:00

Add nvmem_cell_read_u16() helper to ease read of an u16 value on consumer side. This is inspired by nvmem_cell_read_u32() function. This helper is useful on stm32 that has 16 bits data cells stored in non volatile memory. Signed-off-by: Fabrice Gasnier Signed-off-by: Srinivas Kandagatla Signed-off-by: Greg Kroah-Hartman

nvmem: core: don't check the return value of notifier chain call

2019-02-19T13:50:11+00:00

blocking_notifier_call_chain() returns the value returned by the last registered callback. A positive return value doesn't indicate an error and an nvmem device should correctly register irrespective of any notifier callback failures. Drop the retval check. Fixes: bee1138bea15 ("nvmem: add a notifier chain") Cc: stable@vger.kernel.org Signed-off-by: Bartosz Golaszewski Acked-by: Srinivas Kandagatla Signed-off-by: Greg Kroah-Hartman