linux/drivers/tty/serial/sh-sci.c, branch v5.1

serial: sh-sci: Fix HSCIF RX sampling point adjustment

2019-04-16T13:24:38Z

The calculation of the sampling point has min() and max() exchanged. Fix this by using the clamp() helper instead. Fixes: 63ba1e00f178a448 ("serial: sh-sci: Support for HSCIF RX sampling point adjustment") Signed-off-by: Geert Uytterhoeven Reviewed-by: Ulrich Hecht Reviewed-by: Wolfram Sang Acked-by: Dirk Behme Cc: stable Reviewed-by: Simon Horman Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Fix HSCIF RX sampling point calculation

2019-04-16T13:24:38Z

There are several issues with the formula used for calculating the deviation from the intended rate: 1. While min_err and last_stop are signed, srr and baud are unsigned. Hence the signed values are promoted to unsigned, which will lead to a bogus value of deviation if min_err is negative, 2. Srr is the register field value, which is one less than the actual sampling rate factor, 3. The divisions do not use rounding. Fix this by casting unsigned variables to int, adding one to srr, and using a single DIV_ROUND_CLOSEST(). Fixes: 63ba1e00f178a448 ("serial: sh-sci: Support for HSCIF RX sampling point adjustment") Signed-off-by: Geert Uytterhoeven Reviewed-by: Mukesh Ojha Cc: stable Reviewed-by: Ulrich Hecht Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Fix setting SCSCR_TIE while transferring data

2019-03-19T14:37:44Z

We disable transmission interrupt (clear SCSCR_TIE) after all data has been transmitted (if uart_circ_empty(xmit)). While transmitting, if the data is still in the tty buffer, re-enable the SCSCR_TIE bit, which was done at sci_start_tx(). This is unnecessary processing, wasting CPU operation if the data transmission length is large. And further, transmit end, FIFO empty bits disabling have also been performed in the step above. Signed-off-by: Hoan Nguyen An Cc: stable Signed-off-by: Greg Kroah-Hartman

Merge 5.0-rc6 into tty-next

2019-02-11T08:26:45Z

We need the tty fixes in here for other patches to be based on. Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Do not free irqs that have already been freed

2019-01-30T08:35:46Z

Since IRQs might be muxed on some parts, we need to pay attention when we are freeing them. Otherwise we get the ugly WARNING "Trying to free already-free IRQ 20". Fixes: 628c534ae735 ("serial: sh-sci: Improve support for separate TEI and DRI interrupts") Cc: stable Signed-off-by: Chris Brandt Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Make RX/TX DMA function names consistent

2019-01-08T15:56:52Z

Most RX/TX-specific DMA functions are prefixed with "sci_dma_[rt]x_". Rename the exceptions to increase consistency. Signed-off-by: Geert Uytterhoeven Reviewed-by: Simon Horman Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Fix fallback to PIO in sci_dma_rx_complete()

2019-01-08T15:56:52Z

When submitting a DMA request fails in sci_dma_rx_complete(), the driver tries to fall back to PIO, but that does not work: no more data will be received, or the kernel will even crash. Fix this similar as in (but not identical to) sci_submit_rx(): - On SCIF, PIO cannot take over if any DMA transactions are pending, hence they must be terminated first. - All active cookies must be invalidated, else rx_timer_fn() may trigger a NULL pointer dereference. - Restarting the port is not needed, as it is already running, but serial port interrupts must be directed back from the DMA engine to the CPU. Signed-off-by: Geert Uytterhoeven Reviewed-by: Simon Horman Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Extract sci_dma_rx_reenable_irq()

2019-01-08T15:56:52Z

Extract the functionality to direct new serial port interrupts back to the CPU into its own helper, to prepare for using it from a second callsite. Signed-off-by: Geert Uytterhoeven Reviewed-by: Simon Horman Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Extract sci_dma_rx_chan_invalidate()

2019-01-08T15:56:52Z

The cookies and channel pointer for the DMA receive channel are invalidated in two places, and one more is planned. Extract this functionality in a common helper. Signed-off-by: Geert Uytterhoeven Reviewed-by: Simon Horman Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Resume PIO in sci_rx_interrupt() on DMA failure

2018-12-17T14:04:11Z

On (H)SCIF, sci_submit_rx() is called in the receive interrupt handler. Hence if DMA submission fails, the interrupt handler should resume handling reception using PIO, else no more data is received. Make sci_submit_rx() return an error indicator, so the receive interrupt handler can act appropriately. Signed-off-by: Geert Uytterhoeven Reviewed-by: Simon Horman Acked-by: Wolfram Sang Signed-off-by: Greg Kroah-Hartman