Re: [PATCH v5 6/6] tty/serial: atmel: changed the driver to work under at91-usart mfd

From: Richard Genoud
Date: Wed Jun 06 2018 - 07:02:59 EST


Typo in the subject:
changed->change


On 04/06/2018 18:59, Radu Pirea wrote:
> This patch modifies the place where resources and device tree properties
> are searched.
>
> Signed-off-by: Radu Pirea <radu.pirea@xxxxxxxxxxxxx>
> ---
> drivers/tty/serial/Kconfig | 1 +
> drivers/tty/serial/atmel_serial.c | 41 ++++++++++++++++++-------------
> 2 files changed, 25 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
> index 3682fd3e960c..25e55332f8b1 100644
> --- a/drivers/tty/serial/Kconfig
> +++ b/drivers/tty/serial/Kconfig
> @@ -119,6 +119,7 @@ config SERIAL_ATMEL
> depends on ARCH_AT91 || COMPILE_TEST
> select SERIAL_CORE
> select SERIAL_MCTRL_GPIO if GPIOLIB
> + select MFD_AT91_USART
> help
> This enables the driver for the on-chip UARTs of the Atmel
> AT91 processors.
> diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
> index df46a9e88c34..5c74e03396ef 100644
> --- a/drivers/tty/serial/atmel_serial.c
> +++ b/drivers/tty/serial/atmel_serial.c
> @@ -193,8 +193,8 @@ static struct console atmel_console;
>
> #if defined(CONFIG_OF)
> static const struct of_device_id atmel_serial_dt_ids[] = {
> - { .compatible = "atmel,at91rm9200-usart" },
> - { .compatible = "atmel,at91sam9260-usart" },
> + { .compatible = "atmel,at91rm9200-usart-serial" },
> + { .compatible = "atmel,at91sam9260-usart-serial" },
Sorry, I didn't catch that before, but we can drop "atmel,at91sam9260-usart-serial" don't we ?
Only "atmel,at91rm9200-usart-serial" is used in the MFD driver.

> { /* sentinel */ }
> };
> #endif
> @@ -915,6 +915,7 @@ static void atmel_tx_dma(struct uart_port *port)
> static int atmel_prepare_tx_dma(struct uart_port *port)
> {
> struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
> + struct device *mfd_dev = port->dev->parent;
> dma_cap_mask_t mask;
> struct dma_slave_config config;
> int ret, nent;
> @@ -922,7 +923,7 @@ static int atmel_prepare_tx_dma(struct uart_port *port)
> dma_cap_zero(mask);
> dma_cap_set(DMA_SLAVE, mask);
>
> - atmel_port->chan_tx = dma_request_slave_channel(port->dev, "tx");
> + atmel_port->chan_tx = dma_request_slave_channel(mfd_dev, "tx");
> if (atmel_port->chan_tx == NULL)
> goto chan_err;
> dev_info(port->dev, "using %s for tx DMA transfers\n",
> @@ -1093,6 +1094,7 @@ static void atmel_rx_from_dma(struct uart_port *port)
> static int atmel_prepare_rx_dma(struct uart_port *port)
> {
> struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
> + struct device *mfd_dev = port->dev->parent;
> struct dma_async_tx_descriptor *desc;
> dma_cap_mask_t mask;
> struct dma_slave_config config;
> @@ -1104,7 +1106,7 @@ static int atmel_prepare_rx_dma(struct uart_port *port)
> dma_cap_zero(mask);
> dma_cap_set(DMA_CYCLIC, mask);
>
> - atmel_port->chan_rx = dma_request_slave_channel(port->dev, "rx");
> + atmel_port->chan_rx = dma_request_slave_channel(mfd_dev, "rx");
> if (atmel_port->chan_rx == NULL)
> goto chan_err;
> dev_info(port->dev, "using %s for rx DMA transfers\n",
> @@ -1631,7 +1633,7 @@ static void atmel_tasklet_tx_func(unsigned long data)
> static void atmel_init_property(struct atmel_uart_port *atmel_port,
> struct platform_device *pdev)
> {
> - struct device_node *np = pdev->dev.of_node;
> + struct device_node *np = pdev->dev.parent->of_node;
I think this is not needed anymore (cf atmel_probe())

>
> /* DMA/PDC usage specification */
> if (of_property_read_bool(np, "atmel,use-dma-rx")) {
> @@ -2222,8 +2224,8 @@ static const char *atmel_type(struct uart_port *port)
> */
> static void atmel_release_port(struct uart_port *port)
> {
> - struct platform_device *pdev = to_platform_device(port->dev);
> - int size = pdev->resource[0].end - pdev->resource[0].start + 1;
> + struct platform_device *mpdev = to_platform_device(port->dev->parent);
> + int size = resource_size(mpdev->resource);
>
> release_mem_region(port->mapbase, size);
>
> @@ -2238,8 +2240,8 @@ static void atmel_release_port(struct uart_port *port)
> */
> static int atmel_request_port(struct uart_port *port)
> {
> - struct platform_device *pdev = to_platform_device(port->dev);
> - int size = pdev->resource[0].end - pdev->resource[0].start + 1;
> + struct platform_device *mpdev = to_platform_device(port->dev->parent);
> + int size = resource_size(mpdev->resource);
>
> if (!request_mem_region(port->mapbase, size, "atmel_serial"))
> return -EBUSY;
> @@ -2341,27 +2343,28 @@ static int atmel_init_port(struct atmel_uart_port *atmel_port,
> {
> int ret;
> struct uart_port *port = &atmel_port->uart;
> + struct platform_device *mpdev = to_platform_device(pdev->dev.parent);
>
> atmel_init_property(atmel_port, pdev);
> atmel_set_ops(port);
>
> - uart_get_rs485_mode(&pdev->dev, &port->rs485);
> + uart_get_rs485_mode(&mpdev->dev, &port->rs485);
>
> port->iotype = UPIO_MEM;
> port->flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP;
> port->ops = &atmel_pops;
> port->fifosize = 1;
> port->dev = &pdev->dev;
> - port->mapbase = pdev->resource[0].start;
> - port->irq = pdev->resource[1].start;
> + port->mapbase = mpdev->resource[0].start;
> + port->irq = mpdev->resource[1].start;
> port->rs485_config = atmel_config_rs485;
> - port->membase = NULL;
> + port->membase = NULL;
>
> memset(&atmel_port->rx_ring, 0, sizeof(atmel_port->rx_ring));
>
> /* for console, the clock could already be configured */
> if (!atmel_port->clk) {
> - atmel_port->clk = clk_get(&pdev->dev, "usart");
> + atmel_port->clk = clk_get(&mpdev->dev, "usart");
> if (IS_ERR(atmel_port->clk)) {
> ret = PTR_ERR(atmel_port->clk);
> atmel_port->clk = NULL;
> @@ -2652,11 +2655,13 @@ static int atmel_serial_resume(struct platform_device *pdev)
> static void atmel_serial_probe_fifos(struct atmel_uart_port *atmel_port,
> struct platform_device *pdev)
> {
> + struct device *dev = pdev->dev.parent;
> +
Ditto

> atmel_port->fifo_size = 0;
> atmel_port->rts_low = 0;
> atmel_port->rts_high = 0;
>
> - if (of_property_read_u32(pdev->dev.of_node,
> + if (of_property_read_u32(dev->of_node,
Ditto
> "atmel,fifo-size",
> &atmel_port->fifo_size))
> return;
> @@ -2694,13 +2699,15 @@ static void atmel_serial_probe_fifos(struct atmel_uart_port *atmel_port,
> static int atmel_serial_probe(struct platform_device *pdev)
> {
> struct atmel_uart_port *atmel_port;
> - struct device_node *np = pdev->dev.of_node;
> + struct device_node *np = pdev->dev.parent->of_node;
> void *data;
> int ret = -ENODEV;
> bool rs485_enabled;
>
> BUILD_BUG_ON(ATMEL_SERIAL_RINGSIZE & (ATMEL_SERIAL_RINGSIZE - 1));
>
> + pdev->dev.of_node = np;
> +
As atmel_serial device's of_node is now the parent node, the changes
in atmel_init_property() and atmel_serial_probe_fifos() are not needed anymore.
And maybe add a comment to explain that this is part of a MFD and all
the attributes are in the parent node, so we're using the MFD device node
instead of this device node.

> ret = of_alias_get_id(np, "serial");
> if (ret < 0)
> /* port id not found in platform data nor device-tree aliases:
> @@ -2845,7 +2852,7 @@ static struct platform_driver atmel_serial_driver = {
> .suspend = atmel_serial_suspend,
> .resume = atmel_serial_resume,
> .driver = {
> - .name = "atmel_usart",
> + .name = "atmel_usart_serial",
> .of_match_table = of_match_ptr(atmel_serial_dt_ids),
> },
> };
>

Thanks !

Richard.