[PATCH 1/6] serial: 8250_dw: add support for clk api

Russell King - ARM Linux
2013-03-15T22:39:17Z

On Fri, Mar 15, 2013 at 09:06:23PM +0100, Maxime Ripard wrote:
> + /* clock got configured through clk api, all done */
> + if (p->uartclk)

if (IS_ERR(p->uartclk))

> + return 0;
> +
> + /* try to find out clock frequency from DT as fallback */
> if (of_property_read_u32(np, "clock-frequency", &val)) {
> - dev_err(p->dev, "no clock-frequency property set\n");
> + dev_err(p->dev, "clk or clock-frequency not defined\n");
> return -EINVAL;
> }
> p->uartclk = val;
> @@ -294,9 +301,21 @@ static int dw8250_probe(struct platform_device *pdev)
> if (!uart.port.membase)
> return -ENOMEM;
>
> + data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
> + if (!data)
> + return -ENOMEM;
> +
> + data->clk = devm_clk_get(&pdev->dev, NULL);
> + if (IS_ERR(data->clk))
> + data->clk = NULL;
> + else
> + clk_prepare_enable(data->clk);

if (!IS_ERR(data->clk))
clk_prepare_enable(data->clk);

> +
> uart.port.iotype = UPIO_MEM;
> uart.port.serial_in = dw8250_serial_in;
> uart.port.serial_out = dw8250_serial_out;
> + uart.port.private_data = data;
> + uart.port.uartclk = clk_get_rate(data->clk);

What if data->clk is invalid?

if (!IS_ERR(data->clk)
uart.port.uartclk = clk_get_rate(data->clk);

>
> dw8250_setup_port(&uart);
>
> @@ -312,12 +331,6 @@ static int dw8250_probe(struct platform_device *pdev)
> return -ENODEV;
> }
>
> - data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
> - if (!data)
> - return -ENOMEM;
> -
> - uart.port.private_data = data;
> -
> data->line = serial8250_register_8250_port(&uart);
> if (data->line < 0)
> return data->line;
> @@ -333,6 +346,8 @@ static int dw8250_remove(struct platform_device *pdev)
>
> serial8250_unregister_port(data->line);
>

if (!IS_ERR(data->clk)

> + clk_disable_unprepare(data->clk);
> +
> return 0;
> }
>
> --
> 1.7.10.4
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel