kernel/linux.git/drivers/auxdisplay, branch v5.15.209

auxdisplay: arm-charlcd: fix release_mem_region() size

2026-03-04T12:19:20+00:00

[ Upstream commit b5c23a4d291d2ac1dfdd574a68a3a68c8da3069e ] It seems like, after the request_mem_region(), the corresponding release_mem_region() must take the same size. This was done in (now removed due to previous refactoring) charlcd_remove() but not in the error path in charlcd_probe(). Fixes: ce8962455e90 ("ARM: 6214/2: driver for the character LCD found in ARM refdesigns") Signed-off-by: Thomas Fourier Reviewed-by: Geert Uytterhoeven Signed-off-by: Andy Shevchenko Signed-off-by: Sasha Levin

auxdisplay: charlcd: Partially revert "Move hwidth and bwidth to struct hd44780_common"

2025-06-04T12:37:57+00:00

[ Upstream commit 09965a142078080fe7807bab0f6f1890cb5987a4 ] Commit 2545c1c948a6 ("auxdisplay: Move hwidth and bwidth to struct hd44780_common") makes charlcd_alloc() argument-less effectively dropping the single allocation for the struct charlcd_priv object along with the driver specific one. Restore that behaviour here. Signed-off-by: Andy Shevchenko Reviewed-by: Geert Uytterhoeven Signed-off-by: Sasha Levin

auxdisplay: hd44780: Fix an API misuse in hd44780.c

2025-05-02T05:44:26+00:00

[ Upstream commit 9b98a7d2e5f4e2beeff88f6571da0cdc5883c7fb ] Variable allocated by charlcd_alloc() should be released by charlcd_free(). The following patch changed kfree() to charlcd_free() to fix an API misuse. Fixes: 718e05ed92ec ("auxdisplay: Introduce hd44780_common.[ch]") Cc: stable@vger.kernel.org Signed-off-by: Haoxiang Li Reviewed-by: Geert Uytterhoeven Signed-off-by: Andy Shevchenko Signed-off-by: Sasha Levin

auxdisplay: hd44780: Convert to platform remove callback returning void

2025-05-02T05:44:25+00:00

[ Upstream commit 9ea02f7cc39d484d16e8a14f3713fefcd33407c0 ] The .remove() callback for a platform driver returns an int which makes many driver authors wrongly assume it's possible to do error handling by returning an error code. However the value returned is ignored (apart from emitting a warning) and this typically results in resource leaks. To improve here there is a quest to make the remove callback return void. In the first step of this quest all drivers are converted to .remove_new(), which already returns void. Eventually after all drivers are converted, .remove_new() will be renamed to .remove(). Trivially convert this driver from always returning zero in the remove callback to the void returning variant. Signed-off-by: Uwe Kleine-König Reviewed-by: Geert Uytterhoeven Signed-off-by: Andy Shevchenko Stable-dep-of: 9b98a7d2e5f4 ("auxdisplay: hd44780: Fix an API misuse in hd44780.c") Signed-off-by: Sasha Levin

auxdisplay: hd44780: Fix potential memory leak in hd44780_remove()

2023-03-11T12:57:22+00:00

[ Upstream commit ddf75a86aba2cfb7ec4497e8692b60c8c8fe0ee7 ] hd44780_probe() allocates a memory chunk for hd with kzalloc() and makes "lcd->drvdata->hd44780" point to it. When we call hd44780_remove(), we should release all relevant memory and resource. But "lcd->drvdata ->hd44780" is not released, which will lead to a memory leak. We should release the "lcd->drvdata->hd44780" in hd44780_remove() to fix the memory leak bug. Fixes: 718e05ed92ec ("auxdisplay: Introduce hd44780_common.[ch]") Reviewed-by: Andy Shevchenko Reported-by: kernel test robot Signed-off-by: Jianglei Nie Signed-off-by: Miguel Ojeda Signed-off-by: Sasha Levin

auxdisplay: lcd2s: Use proper API to free the instance of charlcd object

2022-03-08T18:12:47+00:00

commit 9ed331f8a0fb674f4f06edf05a1687bf755af27b upstream. While it might work, the current approach is fragile in a few ways: - whenever members in the structure are shuffled, the pointer will be wrong - the resource freeing may include more than covered by kfree() Fix this by using charlcd_free() call instead of kfree(). Fixes: 8c9108d014c5 ("auxdisplay: add a driver for lcd2s character display") Cc: Lars Poeschel Signed-off-by: Andy Shevchenko Signed-off-by: Miguel Ojeda Signed-off-by: Greg Kroah-Hartman

auxdisplay: lcd2s: Fix memory leak in ->remove()

2022-03-08T18:12:47+00:00

commit 898c0a15425a5bcaa8d44bd436eae5afd2483796 upstream. Once allocated the struct lcd2s_data is never freed. Fix the memory leak by switching to devm_kzalloc(). Fixes: 8c9108d014c5 ("auxdisplay: add a driver for lcd2s character display") Cc: Lars Poeschel Signed-off-by: Andy Shevchenko Signed-off-by: Miguel Ojeda Signed-off-by: Greg Kroah-Hartman

auxdisplay: lcd2s: Fix lcd2s_redefine_char() feature

2022-03-08T18:12:47+00:00

commit 4424c35ead667ba2e8de7ab8206da66453e6f728 upstream. It seems that the lcd2s_redefine_char() has never been properly tested. The buffer is filled by DEF_CUSTOM_CHAR command followed by the character number (from 0 to 7), but immediately after that these bytes are rewritten by the decoded hex stream. Fix the index to fill the buffer after the command and number. Fixes: 8c9108d014c5 ("auxdisplay: add a driver for lcd2s character display") Cc: Lars Poeschel Signed-off-by: Andy Shevchenko Reviewed-by: Geert Uytterhoeven [fixed typo in commit message] Signed-off-by: Miguel Ojeda Signed-off-by: Greg Kroah-Hartman

auxdisplay: charlcd: checking for pointer reference before dereferencing

2022-01-11T14:35:17+00:00

[ Upstream commit 4daa9ff89ef27be43c15995412d6aee393a78200 ] Check if the pointer lcd->ops->init_display exists before dereferencing it. If a driver called charlcd_init() without defining the ops, this would return segmentation fault, as happened to me when implementing a charlcd driver. Checking the pointer before dereferencing protects from segmentation fault. Signed-off-by: Luiz Sampaio Signed-off-by: Miguel Ojeda Signed-off-by: Sasha Levin

auxdisplay: ht16k33: Fix frame buffer device blanking

2021-11-18T18:17:02+00:00

[ Upstream commit 840fe258332544aa7321921e1723d37b772af7a9 ] As the ht16k33 frame buffer sub-driver does not register an fb_ops.fb_blank() handler, blanking does not work: $ echo 1 > /sys/class/graphics/fb0/blank sh: write error: Invalid argument Fix this by providing a handler that always returns zero, to make sure blank events will be sent to the actual device handling the backlight. Reported-by: Robin van der Gracht Suggested-by: Robin van der Gracht Fixes: 8992da44c6805d53 ("auxdisplay: ht16k33: Driver for LED controller") Signed-off-by: Geert Uytterhoeven Signed-off-by: Miguel Ojeda Signed-off-by: Sasha Levin