linux/drivers/tty/serial/sh-sci.c, branch v5.5

Merge 5.4-rc5 into driver-core-next

2019-10-27T17:54:13Z

We want the sysfs fix in here as well to build on top of. Signed-off-by: Greg Kroah-Hartman

sh: add the sh_ prefix to early platform symbols

2019-10-07T11:50:48Z

Old early platform device support is now sh-specific. Before moving on to implementing new early platform framework based on real platform devices, prefix all early platform symbols with 'sh_'. Signed-off-by: Bartosz Golaszewski Cc: Rich Felker Link: https://lore.kernel.org/r/20191003092913.10731-3-brgl@bgdev.pl Signed-off-by: Greg Kroah-Hartman

drivers: move the early platform device support to arch/sh

2019-10-07T11:50:47Z

SuperH is the only user of the current implementation of early platform device support. We want to introduce a more robust approach to early probing. As the first step - move all the current early platform code to arch/sh. In order not to export internal drivers/base functions to arch code for this temporary solution - copy the two needed routines for driver matching from drivers/base/platform.c to arch/sh/drivers/platform_early.c. Also: call early_platform_cleanup() from subsys_initcall() so that it's called after all early devices are probed. Signed-off-by: Bartosz Golaszewski Cc: Rich Felker Link: https://lore.kernel.org/r/20191003092913.10731-2-brgl@bgdev.pl Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Use platform_get_irq_optional() for optional interrupts

2019-10-04T13:02:28Z

As platform_get_irq() now prints an error when the interrupt does not exist, scary warnings may be printed for optional interrupts: sh-sci e6550000.serial: IRQ index 1 not found sh-sci e6550000.serial: IRQ index 2 not found sh-sci e6550000.serial: IRQ index 3 not found sh-sci e6550000.serial: IRQ index 4 not found sh-sci e6550000.serial: IRQ index 5 not found Fix this by calling platform_get_irq_optional() instead for all but the first interrupts, which are optional. Fixes: 7723f4c5ecdb8d83 ("driver core: platform: Add an error message to platform_get_irq*()") Signed-off-by: Geert Uytterhoeven Reviewed-by: Stephen Boyd Reviewed-by: Yoshihiro Shimoda Tested-by: Yoshihiro Shimoda Link: https://lore.kernel.org/r/20191001180743.1041-1-geert+renesas@glider.be Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Don't check for mctrl_gpio_to_gpiod() returning error

2019-09-04T10:43:54Z

Since commit 1d267ea6539f2663 ("serial: mctrl-gpio: simplify init routine"), mctrl_gpio_init() returns failure if the assignment to any member of the gpio array results in an error pointer. Since commit c359522194593815 ("serial: mctrl_gpio: Avoid probe failures in case of missing gpiolib"), mctrl_gpio_to_gpiod() returns NULL in the !CONFIG_GPIOLIB case. Hence there is no longer a need to check for mctrl_gpio_to_gpiod() returning an error value. A simple NULL check is sufficient. This follows the spirit of commit 445df7ff3fd1a0a9 ("serial: mctrl-gpio: drop usages of IS_ERR_OR_NULL") in the mctrl-gpio core. Signed-off-by: Geert Uytterhoeven Link: https://lore.kernel.org/r/20190814092924.13857-4-geert+renesas@glider.be Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Don't check for mctrl_gpio_init() returning -ENOSYS

2019-09-04T10:43:50Z

Now that the mctrl_gpio code returns NULL instead of ERR_PTR(-ENOSYS) if CONFIG_GPIOLIB is disabled, we can safely remove this check. Signed-off-by: Frieder Schrempf Acked-by: Uwe Kleine-Knig Link: https://lore.kernel.org/r/20190802100349.8659-3-frieder.schrempf@kontron.de Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Use DEVICE_ATTR_RW() for rx_fifo_trigger

2019-09-04T10:43:50Z

While commit b6b996b6cdeecf7e ("treewide: Use DEVICE_ATTR_RW") converted the rx_fifo_timeout attribute, it forgot to convert rx_fifo_trigger due to a slightly different function naming. Signed-off-by: Geert Uytterhoeven Reviewed-by: Ulrich Hecht Link: https://lore.kernel.org/r/20190731124555.14349-1-geert+renesas@glider.be Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: use driver core functions, not sysfs ones.

2019-09-04T10:43:49Z

This is a driver, do not call "raw" sysfs functions, instead call driver core ones. Specifically convert the use of sysfs_create_file() and sysfs_remove_file() to use device_create_file() and device_remove_file() Cc: Jiri Slaby Cc: linux-serial@vger.kernel.org Link: https://lore.kernel.org/r/20190704084617.3602-4-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Terminate TX DMA during buffer flushing

2019-07-03T17:31:30Z

While the .flush_buffer() callback clears sci_port.tx_dma_len since commit 1cf4a7efdc71cab8 ("serial: sh-sci: Fix race condition causing garbage during shutdown"), it does not terminate a transmit DMA operation that may be in progress. Fix this by terminating any pending DMA operations, and resetting the corresponding cookie. Signed-off-by: Geert Uytterhoeven Reviewed-by: Eugeniu Rosca Tested-by: Eugeniu Rosca Link: https://lore.kernel.org/r/20190624123540.20629-3-geert+renesas@glider.be Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Fix TX DMA buffer flushing and workqueue races

2019-07-03T17:31:30Z

When uart_flush_buffer() is called, the .flush_buffer() callback zeroes the tx_dma_len field. This may race with the work queue function handling transmit DMA requests: 1. If the buffer is flushed before the first DMA API call, dmaengine_prep_slave_single() may be called with a zero length, causing the DMA request to never complete, leading to messages like: rcar-dmac e7300000.dma-controller: Channel Address Error happen and, with debug enabled: sh-sci e6e88000.serial: sci_dma_tx_work_fn: ffff800639b55000: 0...0, cookie 126 and DMA timeouts. 2. If the buffer is flushed after the first DMA API call, but before the second, dma_sync_single_for_device() may be called with a zero length, causing the transmit data not to be flushed to RAM, and leading to stale data being output. Fix this by: 1. Letting sci_dma_tx_work_fn() return immediately if the transmit buffer is empty, 2. Extending the critical section to cover all DMA preparational work, so tx_dma_len stays consistent for all of it, 3. Using local copies of circ_buf.head and circ_buf.tail, to make sure they match the actual operation above. Reported-by: Eugeniu Rosca Suggested-by: Yoshihiro Shimoda Signed-off-by: Geert Uytterhoeven Reviewed-by: Eugeniu Rosca Tested-by: Eugeniu Rosca Link: https://lore.kernel.org/r/20190624123540.20629-2-geert+renesas@glider.be Signed-off-by: Greg Kroah-Hartman