Re: [PATCH v2 4/6] can: sja1000: fuse of_platform into platform

From: Marc Kleine-Budde
Date: Fri Jan 31 2014 - 07:33:51 EST


On 01/31/2014 11:35 AM, Florian Vaussard wrote:
> The OpenFirmware probe can be merged into the standard platform
> probe to leverage common code.

Good work, as we want to replace the existing driver, I'm quite picky on
this patch, see more comments inline.

Please don't delete of of_platform driver, yet.

> Signed-off-by: Florian Vaussard <florian.vaussard@xxxxxxx>
> ---
> drivers/net/can/sja1000/Kconfig | 13 +-
> drivers/net/can/sja1000/Makefile | 1 -
> drivers/net/can/sja1000/sja1000_of_platform.c | 218 --------------------------
> drivers/net/can/sja1000/sja1000_platform.c | 141 +++++++++++++----
> 4 files changed, 116 insertions(+), 257 deletions(-)
> delete mode 100644 drivers/net/can/sja1000/sja1000_of_platform.c
[...]

> diff --git a/drivers/net/can/sja1000/sja1000_platform.c b/drivers/net/can/sja1000/sja1000_platform.c
> index 779679a..96a92a1 100644
> --- a/drivers/net/can/sja1000/sja1000_platform.c
> +++ b/drivers/net/can/sja1000/sja1000_platform.c
> @@ -27,12 +27,16 @@
> #include <linux/can/dev.h>
> #include <linux/can/platform/sja1000.h>
> #include <linux/io.h>
> +#include <linux/of.h>
> +#include <linux/of_irq.h>
>
> #include "sja1000.h"
>
> #define DRV_NAME "sja1000_platform"
> +#define SJA1000_OFP_CAN_CLOCK (16000000 / 2)

This driver uses "SP" short for sja100_platform as namespace, please
convert.

>
> MODULE_AUTHOR("Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>");
> +MODULE_AUTHOR("Wolfgang Grandegger <wg@xxxxxxxxxxxxxx>");
> MODULE_DESCRIPTION("Socket-CAN driver for SJA1000 on the platform bus");
> MODULE_ALIAS("platform:" DRV_NAME);
> MODULE_LICENSE("GPL v2");
> @@ -67,24 +71,98 @@ static void sp_write_reg32(const struct sja1000_priv *priv, int reg, u8 val)
> iowrite8(val, priv->reg_base + reg * 4);
> }
>
> -static int sp_probe(struct platform_device *pdev)
> +static void sp_populate(struct sja1000_priv *priv,
> + struct sja1000_platform_data *pdata,
> + unsigned long resource_mem_flags)
> +{
> + /* The CAN clock frequency is half the oscillator clock frequency */
> + priv->can.clock.freq = pdata->osc_freq / 2;
> + priv->ocr = pdata->ocr;
> + priv->cdr = pdata->cdr;
> +
> + switch (resource_mem_flags & IORESOURCE_MEM_TYPE_MASK) {
> + case IORESOURCE_MEM_32BIT:
> + priv->read_reg = sp_read_reg32;
> + priv->write_reg = sp_write_reg32;
> + break;
> + case IORESOURCE_MEM_16BIT:
> + priv->read_reg = sp_read_reg16;
> + priv->write_reg = sp_write_reg16;
> + break;
> + case IORESOURCE_MEM_8BIT:
> + default:
> + priv->read_reg = sp_read_reg8;
> + priv->write_reg = sp_write_reg8;
> + break;
> + }
> +}
> +
> +#if defined(CONFIG_OF)

The driver also compiles on systems without CONFIG_OF without these
defines. Please remove.

> +static void sp_populate_of(struct sja1000_priv *priv, struct device_node *of)
> {
> int err;
> + u32 prop;
> +
> + priv->read_reg = sp_read_reg8;
> + priv->write_reg = sp_write_reg8;
> +
> + err = of_property_read_u32(of, "nxp,external-clock-frequency", &prop);
> + if (!err)
> + priv->can.clock.freq = prop / 2;
> + else
> + priv->can.clock.freq = SJA1000_OFP_CAN_CLOCK; /* default */
> +
> + err = of_property_read_u32(of, "nxp,tx-output-mode", &prop);
> + if (!err)
> + priv->ocr |= prop & OCR_MODE_MASK;
> + else
> + priv->ocr |= OCR_MODE_NORMAL; /* default */
> +
> + err = of_property_read_u32(of, "nxp,tx-output-config", &prop);
> + if (!err)
> + priv->ocr |= (prop << OCR_TX_SHIFT) & OCR_TX_MASK;
> + else
> + priv->ocr |= OCR_TX0_PULLDOWN; /* default */
> +
> + err = of_property_read_u32(of, "nxp,clock-out-frequency", &prop);
> + if (!err && prop) {
> + u32 divider = priv->can.clock.freq * 2 / prop;
> +
> + if (divider > 1)
> + priv->cdr |= divider / 2 - 1;
> + else
> + priv->cdr |= CDR_CLKOUT_MASK;
> + } else {
> + priv->cdr |= CDR_CLK_OFF; /* default */
> + }
> +
> + if (!of_property_read_bool(of, "nxp,no-comparator-bypass"))
> + priv->cdr |= CDR_CBP; /* default */
> +}
> +#else
> +static void sp_populate_of(struct sja1000_priv *priv, device_node *of)
> +{
> +}
> +#endif
> +
> +static int sp_probe(struct platform_device *pdev)
> +{
> + int err, irq = 0;
> void __iomem *addr;
> struct net_device *dev;
> struct sja1000_priv *priv;
> - struct resource *res_mem, *res_irq;
> + struct resource *res_mem, *res_irq = 0;

Please use NULL to initialize pointers.

> struct sja1000_platform_data *pdata;
> + struct device_node *of = pdev->dev.of_node;
>
> pdata = dev_get_platdata(&pdev->dev);
> - if (!pdata) {
> + if (!pdata && !of) {
> dev_err(&pdev->dev, "No platform data provided!\n");
> return -ENODEV;
> }
>
> res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> - res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
> - if (!res_mem || !res_irq)
> + if (!res_mem)
> return -ENODEV;
>
> if (!devm_request_mem_region(&pdev->dev, res_mem->start,
> @@ -96,36 +174,34 @@ static int sp_probe(struct platform_device *pdev)
> if (!addr)
> return -ENOMEM;
>
> + if (of)
> + irq = irq_of_parse_and_map(of, 0);
> + else
> + res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
> +
> + if (!irq && !res_irq)
> + return -ENODEV;
> +
> dev = alloc_sja1000dev(0);
> if (!dev)
> return -ENOMEM;
> priv = netdev_priv(dev);
>
> - dev->irq = res_irq->start;
> - priv->irq_flags = res_irq->flags & IRQF_TRIGGER_MASK;
> - if (res_irq->flags & IORESOURCE_IRQ_SHAREABLE)
> - priv->irq_flags |= IRQF_SHARED;
> + if (res_irq) {
> + irq = res_irq->start;
> + priv->irq_flags = res_irq->flags & IRQF_TRIGGER_MASK;
> + if (res_irq->flags & IORESOURCE_IRQ_SHAREABLE)
> + priv->irq_flags |= IRQF_SHARED;
> + } else
> + priv->irq_flags = IRQF_SHARED;

Please add { } for else, too.

> +
> + dev->irq = irq;
> priv->reg_base = addr;
> - /* The CAN clock frequency is half the oscillator clock frequency */
> - priv->can.clock.freq = pdata->osc_freq / 2;
> - priv->ocr = pdata->ocr;
> - priv->cdr = pdata->cdr;
>
> - switch (res_mem->flags & IORESOURCE_MEM_TYPE_MASK) {
> - case IORESOURCE_MEM_32BIT:
> - priv->read_reg = sp_read_reg32;
> - priv->write_reg = sp_write_reg32;
> - break;
> - case IORESOURCE_MEM_16BIT:
> - priv->read_reg = sp_read_reg16;
> - priv->write_reg = sp_write_reg16;
> - break;
> - case IORESOURCE_MEM_8BIT:
> - default:
> - priv->read_reg = sp_read_reg8;
> - priv->write_reg = sp_write_reg8;
> - break;
> - }
> + if (of)
> + sp_populate_of(priv, of);
> + else
> + sp_populate(priv, pdata, res_mem->flags);
>
> platform_set_drvdata(pdev, dev);
> SET_NETDEV_DEV(dev, &pdev->dev);
> @@ -156,12 +232,21 @@ static int sp_remove(struct platform_device *pdev)
> return 0;
> }
>
> +#if defined(CONFIG_OF)

Please remove the ifdef.

> +static struct of_device_id sja1000_ofp_table[] = {

Please rename into sp_of_table or something similar.

> + {.compatible = "nxp,sja1000"},
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, sja1000_ofp_table);
> +#endif
> +
> static struct platform_driver sp_driver = {
> .probe = sp_probe,
> .remove = sp_remove,
> .driver = {
> .name = DRV_NAME,
> .owner = THIS_MODULE,
> + .of_match_table = of_match_ptr(sja1000_ofp_table),

The of_match_ptr is not needed anymore, please remove.

> },
> };
>
>

Marc

--
Pengutronix e.K. | Marc Kleine-Budde |
Industrial Linux Solutions | Phone: +49-231-2826-924 |
Vertretung West/Dortmund | Fax: +49-5121-206917-5555 |
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