[PATCH v6 1/3] serial: sh-sci: Add OF support
Laurent Pinchart
laurent.pinchart at ideasonboard.com
Wed Mar 6 07:10:55 EST 2013
Hi Bastian,
Thanks for the patch.
On Wednesday 06 March 2013 12:30:35 Bastian Hecht wrote:
> We add the capabilty to probe Renesas SCI devices using Device Tree setup.
>
> Signed-off-by: Bastian Hecht <hechtb+renesas at gmail.com>
> Reviewed-by: Paul Mundt <lethal at linux-sh.org>
> Acked-by: Arnd Bergmann <arnd at arndb.de>
> ---
> v6:
> putting it all together: I posted v5 as an incremental patch - here
> the full version based on Simon Horman's tree topic/intc-of.
>
> I will post another incremental version as well.
>
> - rename sci at xxxxxxxx to serial at xxxxxxxx
> - stick to scbrr-algorithm
>
> .../bindings/tty/serial/renesas,sci-serial.txt | 47 +++++++
> drivers/tty/serial/sh-sci.c | 146
> +++++++++++++++++++- include/linux/serial_sci.h |
> 4 +
> 3 files changed, 193 insertions(+), 4 deletions(-)
> create mode 100644
> Documentation/devicetree/bindings/tty/serial/renesas,sci-serial.txt
>
> diff --git
> a/Documentation/devicetree/bindings/tty/serial/renesas,sci-serial.txt
> b/Documentation/devicetree/bindings/tty/serial/renesas,sci-serial.txt new
> file mode 100644
> index 0000000..d80039e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/tty/serial/renesas,sci-serial.txt
> @@ -0,0 +1,47 @@
> +* Renesas SH-Mobile Serial Communication Interface
> +
> +Required properties:
> +- compatible : Should be "renesas,sci-<port type>-uart", where <port type>
> is + "sci", "scif", "irda", "scifa", "scifb"
> + or for legacy devices
> + "sh2_scif_fifodata", "sh3_scif", "sh4_scif", "sh4_scif_no_scsptr",
> + "sh4_scif_fifodata", "sh7705_scif".
> +- reg : Address and length of the register set for the device
> +- interrupts : Should contain the following IRQs in this order:
> + ERI: receive-error interrupt
> + RXI: receive-FIFO-data-full interrupt
> + TXI: transmit-FIFO-data-empty interrupt
> + BRI: break reception interrupt
> +- interrupt-names: The IRQ names "eri", "rxi", "txi" and "bri".
> +- cell-index : The device id.
> +- renesas,scscr : Should contain a bitfield used by the Serial Control
> Register.
> + b7 = SCSCR_TIE
> + b6 = SCSCR_RIE
> + b5 = SCSCR_TE
> + b4 = SCSCR_RE
> + b3 = SCSCR_REIE
> + b2 = SCSCR_TOIE
> + b1 = SCSCR_CKE1
> + b0 = SCSCR_CKE0
What is that for exactly ?
> +- renesas,scbrr-algorithm : Choose an algorithm ID for the baud rate
> generator.
> + 1 = SCBRR_ALGO_1 ((clk + 16 * bps) / (16 * bps) - 1)
> + 2 = SCBRR_ALGO_2 ((clk + 16 * bps) / (32 * bps) - 1)
> + 3 = SCBRR_ALGO_3 (((clk * 2) + 16 * bps) / (16 * bps) - 1)
> + 4 = SCBRR_ALGO_4 (((clk * 2) + 16 * bps) / (32 * bps) - 1)
> + 5 = SCBRR_ALGO_5 (((clk * 1000 / 32) / bps) - 1)
Isn't it a property specific to our implementation of the driver instead of a
hardware property ? How is one supposed to select the right algorithm ?
> +Optional properties:
> +- renesas,autoconf : Set if device is capable of auto configuration.
> +
> +Example:
> + serial at e6c50000 {
> + compatible = "renesas,sci-scifa-uart";
> + interrupt-parent = <&intca>;
> + reg = <0xe6c50000 0x100>;
> + interrupts = <0x0c20>, <0x0c20>, <0x0c20>, <0x0c20>;
> + interrupt-names = "eri", "rxi", "txi", "bri";
> + cell-index = <1>;
> + renesas,scscr = <0x30>;
> + renesas,scbrr-algorithm = <4>;
> + renesas,autoconf;
> + };
> diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
> index 6147756..03bb740 100644
> --- a/drivers/tty/serial/sh-sci.c
> +++ b/drivers/tty/serial/sh-sci.c
> @@ -52,6 +52,7 @@
> #include <linux/scatterlist.h>
> #include <linux/slab.h>
> #include <linux/gpio.h>
> +#include <linux/of.h>
>
> #ifdef CONFIG_SUPERH
> #include <asm/sh_bios.h>
> @@ -2353,6 +2354,131 @@ static int sci_remove(struct platform_device *dev)
> return 0;
> }
>
> +static const struct of_device_id of_sci_match[] = {
> + { .compatible = "renesas,sci-sci-uart",
> + .data = (void *)SCIx_SCI_REGTYPE },
> + { .compatible = "renesas,sci-scif-uart",
> + .data = (void *)SCIx_SH4_SCIF_REGTYPE, },
> + { .compatible = "renesas,sci-irda-uart",
> + .data = (void *)SCIx_IRDA_REGTYPE },
> + { .compatible = "renesas,sci-scifa-uart",
> + .data = (void *)SCIx_SCIFA_REGTYPE },
> + { .compatible = "renesas,sci-scifb-uart",
> + .data = (void *)SCIx_SCIFB_REGTYPE },
> + { .compatible = "renesas,sci-sh2_scif_fifodata-uart",
> + .data = (void *)SCIx_SH2_SCIF_FIFODATA_REGTYPE },
> + { .compatible = "renesas,sci-sh3_scif-uart",
> + .data = (void *)SCIx_SH3_SCIF_REGTYPE },
> + { .compatible = "renesas,sci-sh4_scif-uart",
> + .data = (void *)SCIx_SH4_SCIF_REGTYPE },
> + { .compatible = "renesas,sci-sh4_scif_no_scsptr-uart",
> + .data = (void *)SCIx_SH4_SCIF_NO_SCSPTR_REGTYPE },
> + { .compatible = "renesas,sci-sh4_scif_fifodata-uart",
> + .data = (void *)SCIx_SH4_SCIF_FIFODATA_REGTYPE },
> + { .compatible = "renesas,sci-sh7705_scif-uart",
> + .data = (void *)SCIx_SH7705_SCIF_REGTYPE },
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, of_sci_match);
> +
> +static struct plat_sci_port *sci_parse_dt(struct platform_device *pdev,
> + int *dev_id)
> +{
> + struct plat_sci_port *p;
> + struct device_node *np = pdev->dev.of_node;
> + const struct of_device_id *match;
> + struct resource *res;
> + const __be32 *prop;
> + int i, irq, val;
> +
> + if (!IS_ENABLED(CONFIG_OF) || !np)
> + return NULL;
> +
> + match = of_match_node(of_sci_match, pdev->dev.of_node);
> + if (!match || !match->data) {
> + dev_err(&pdev->dev, "OF match error\n");
> + return NULL;
> + }
> +
> + p = devm_kzalloc(&pdev->dev, sizeof(struct plat_sci_port), GFP_KERNEL);
> + if (!p) {
> + dev_err(&pdev->dev, "failed to allocate DT config data\n");
> + return NULL;
> + }
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + if (!res) {
> + dev_err(&pdev->dev, "failed to get I/O memory\n");
> + return NULL;
> + }
> + p->mapbase = res->start;
> +
> + for (i = 0; i < SCIx_NR_IRQS; i++) {
> + irq = platform_get_irq(pdev, i);
> + if (irq < 0) {
> + dev_err(&pdev->dev, "failed to get irq data %d\n", i);
> + return NULL;
> + }
> + p->irqs[i] = irq;
> + }
> +
> + prop = of_get_property(np, "cell-index", NULL);
> + if (!prop) {
> + dev_err(&pdev->dev, "required DT prop cell-index missing\n");
> + return NULL;
> + }
> + *dev_id = be32_to_cpup(prop);
> +
> + prop = of_get_property(np, "renesas,scscr", NULL);
> + if (!prop) {
> + dev_err(&pdev->dev, "required DT prop scscr missing\n");
> + return NULL;
> + }
> + p->scscr = be32_to_cpup(prop);
> +
> + prop = of_get_property(np, "renesas,scbrr-algorithm", NULL);
> + if (!prop) {
> + dev_err(&pdev->dev, "required DT prop scbrr-algorithm missing\n");
> + return NULL;
> + }
> + val = be32_to_cpup(prop);
> + if (val <= SCBRR_ALGO_INVALID || val >= SCBRR_NR_ALGOS) {
> + dev_err(&pdev->dev, "DT prop clock-algorithm out of range\n");
> + return NULL;
> + }
> + p->scbrr_algo_id = val;
> +
> + p->flags = UPF_IOREMAP;
> + if (of_get_property(np, "renesas,autoconf", NULL))
> + p->flags |= UPF_BOOT_AUTOCONF;
> +
> + p->regtype = (unsigned int)match->data;
> +
> + switch (p->regtype) {
> + case SCIx_SCI_REGTYPE:
> + p->type = PORT_SCI;
> + break;
> + case SCIx_SH4_SCIF_REGTYPE:
> + p->type = PORT_SCIF;
> + break;
> + case SCIx_IRDA_REGTYPE:
> + p->type = PORT_IRDA;
> + break;
> + case SCIx_SCIFA_REGTYPE:
> + p->type = PORT_SCIFA;
> + break;
> + case SCIx_SCIFB_REGTYPE:
> + p->type = PORT_SCIFB;
> + break;
> + default:
> + /* legacy register sets default to PORT_SCIF */
> + p->type = PORT_SCIF;
> + break;
> + }
> +
> + return p;
> +}
> +
> static int sci_probe_single(struct platform_device *dev,
> unsigned int index,
> struct plat_sci_port *p,
> @@ -2385,9 +2511,9 @@ static int sci_probe_single(struct platform_device
> *dev,
>
> static int sci_probe(struct platform_device *dev)
> {
> - struct plat_sci_port *p = dev->dev.platform_data;
> - struct sci_port *sp = &sci_ports[dev->id];
> - int ret;
> + struct plat_sci_port *p;
> + struct sci_port *sp;
> + int ret, dev_id = dev->id;
>
> /*
> * If we've come here via earlyprintk initialization, head off to
> @@ -2397,9 +2523,20 @@ static int sci_probe(struct platform_device *dev)
> if (is_early_platform_device(dev))
> return sci_probe_earlyprintk(dev);
>
> + if (dev->dev.of_node)
> + p = sci_parse_dt(dev, &dev_id);
> + else
> + p = dev->dev.platform_data;
> +
> + if (!p) {
> + dev_err(&dev->dev, "no setup data supplied\n");
> + return -EINVAL;
> + }
> +
> + sp = &sci_ports[dev_id];
> platform_set_drvdata(dev, sp);
>
> - ret = sci_probe_single(dev, dev->id, p, sp);
> + ret = sci_probe_single(dev, dev_id, p, sp);
> if (ret)
> return ret;
>
> @@ -2451,6 +2588,7 @@ static struct platform_driver sci_driver = {
> .name = "sh-sci",
> .owner = THIS_MODULE,
> .pm = &sci_dev_pm_ops,
> + .of_match_table = of_match_ptr(of_sci_match),
> },
> };
>
> diff --git a/include/linux/serial_sci.h b/include/linux/serial_sci.h
> index eb763ad..857eec4 100644
> --- a/include/linux/serial_sci.h
> +++ b/include/linux/serial_sci.h
> @@ -11,11 +11,15 @@
> #define SCIx_NOT_SUPPORTED (-1)
>
> enum {
> + SCBRR_ALGO_INVALID,
> +
> SCBRR_ALGO_1, /* ((clk + 16 * bps) / (16 * bps) - 1) */
> SCBRR_ALGO_2, /* ((clk + 16 * bps) / (32 * bps) - 1) */
> SCBRR_ALGO_3, /* (((clk * 2) + 16 * bps) / (16 * bps) - 1) */
> SCBRR_ALGO_4, /* (((clk * 2) + 16 * bps) / (32 * bps) - 1) */
> SCBRR_ALGO_5, /* (((clk * 1000 / 32) / bps) - 1) */
> +
> + SCBRR_NR_ALGOS,
> };
>
> #define SCSCR_TIE (1 << 7)
--
Regards,
Laurent Pinchart
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