Re: [PATCH] serial: Add OMAP high-speed UART driver.

From: Tony Lindgren
Date: Mon Mar 01 2010 - 13:45:04 EST


* Govindraj.R <govindraj.raja@xxxxxx> [100301 06:40]:
> --- /dev/null
> +++ b/drivers/serial/omap-serial.c
> +
> +static void serial_omap_stop_tx(struct uart_port *port)
> +{
> + struct uart_omap_port *up = (struct uart_omap_port *)port;
> +
> + if (up->use_dma &&
> + up->uart_dma.tx_dma_channel != OMAP_UART_DMA_CH_FREE) {
> + /*
> + * Check if dma is still active . If yes do nothing,

Looks like an extra space here before the period above.

...

> +static int serial_omap_start_rxdma(struct uart_omap_port *up)
> +{
> + int ret = 0;
> +
> + if (up->uart_dma.rx_dma_channel == -1) {
> + ret = omap_request_dma(up->uart_dma.uart_dma_rx,
> + "UART Rx DMA",
> + (void *)uart_rx_dma_callback, up,
> + &(up->uart_dma.rx_dma_channel));
> + if (ret < 0)
> + return ret;
> +
> + omap_set_dma_src_params(up->uart_dma.rx_dma_channel, 0,
> + OMAP_DMA_AMODE_CONSTANT,
> + up->uart_dma.uart_base, 0, 0);
> + omap_set_dma_dest_params(up->uart_dma.rx_dma_channel, 0,
> + OMAP_DMA_AMODE_POST_INC,
> + up->uart_dma.rx_buf_dma_phys, 0, 0);
> + omap_set_dma_transfer_params(up->uart_dma.rx_dma_channel,
> + OMAP_DMA_DATA_TYPE_S8,
> + up->uart_dma.rx_buf_size, 1,
> + OMAP_DMA_SYNC_ELEMENT,
> + up->uart_dma.uart_dma_rx, 0);
> + }
> + up->uart_dma.prev_rx_dma_pos = up->uart_dma.rx_buf_dma_phys;
> + if (cpu_is_omap44xx())
> + omap_writel(0, OMAP44XX_DMA4_BASE
> + + OMAP_DMA4_CDAC(up->uart_dma.rx_dma_channel));
> + else
> + omap_writel(0, OMAP34XX_DMA4_BASE
> + + OMAP_DMA4_CDAC(up->uart_dma.rx_dma_channel));

NAK. Please don't use omap_read/write for for new code. And do not
tinker with the omap hardware registers directly in the driver.

This needs to be done properly in arch/arm/plat-omap/dma.c instead.

We really don't want drivers tinkering with the omap hardware
registers directly except for the driver block registers.

Regards,

Tony
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