[U-Boot] [PATCH v7] dm: at91: Add driver model support for the spi driver

Wenyou.Yang at microchip.com Wenyou.Yang at microchip.com
Thu Aug 18 03:16:28 CEST 2016


Hi Andreas,

> -----Original Message-----
> From: Andreas Bießmann [mailto:andreas at biessmann.org]
> Sent: 2016年8月16日 5:15
> To: Wenyou Yang <wenyou.yang at atmel.com>; U-Boot Mailing List <u-
> boot at lists.denx.de>
> Cc: Simon Glass <sjg at chromium.org>; Jagan Teki <jteki at openedev.com>
> Subject: Re: [PATCH v7] dm: at91: Add driver model support for the spi driver
> 
> Hi Wenyou,
> 
> On 29.07.16 02:38, Wenyou Yang wrote:
> > Add driver model support while retaining the existing legacy code.
> > This allows the driver to support boards that have converted to driver
> > model as well as those that have not.
> >
> > Signed-off-by: Wenyou Yang <wenyou.yang at atmel.com>
> > Reviewed-by: Simon Glass <sjg at chromium.org>
> 
> This one breaks avr32 boards:
> 
> ---8<---
> 02: dm: at91: Add driver model support for the spi driver
>      avr32:  +   atngw100 atngw100mkii
> +../drivers/spi/atmel_spi.c:17:31: error: asm/arch/at91_spi.h: No such
> file or directory
> +../drivers/spi/atmel_spi.c:18:22: error: asm/gpio.h: No such file or
> directory
> +make[2]: *** [drivers/spi/atmel_spi.o] Error 1
> +make[1]: *** [drivers/spi] Error 2
> +make: *** [sub-make] Error 2
> --->8---

It seems this error is not introduced by this patch.

Can we apply this patch first?

> 
> please fix this
> 
> Andreas
> 
> > ---
> >
> > Changes in v7:
> >  - Move gpio_request_list_by_name() to _probe(), remove
> >    *_ofdata_to_platdata().
> >
> > Changes in v6:
> >  - Remove the two flash related options.
> >
> > Changes in v5:
> >  - Change clk_client.h -> clk.h to adapt to clk API conversion.
> >
> > Changes in v4:
> >  - Collect Reviewed-by tag.
> >  - Update the clk API based on [PATCH] clk: convert API to match
> >    reset/mailbox fstyle (http://patchwork.ozlabs.org/patch/625342/).
> >  - Remove check on dev_get_parent() return.
> >  - Fixed the return value, -ENODEV->-EINVAL.
> >  - Retain #include <asm/arch/clk.h> line.
> >
> > Changes in v3:
> >  - Remove redundant log print.
> >
> > Changes in v2:
> >  - Add clock support.
> >
> >  drivers/spi/Kconfig     |   7 ++
> >  drivers/spi/atmel_spi.c | 295
> > ++++++++++++++++++++++++++++++++++++++++++++++++
> >  2 files changed, 302 insertions(+)
> >
> > diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index
> > aca385d..16ed231 100644
> > --- a/drivers/spi/Kconfig
> > +++ b/drivers/spi/Kconfig
> > @@ -32,6 +32,13 @@ config ATH79_SPI
> >  	  uses driver model and requires a device tree binding to operate.
> >  	  please refer to doc/device-tree-bindings/spi/spi-ath79.txt.
> >
> > +config ATMEL_SPI
> > +	bool "Atmel SPI driver"
> > +	depends on ARCH_AT91
> > +	help
> > +	  Enable the Atmel SPI driver. This driver can be used to access
> > +	  the SPI Flash, such as AT25DF321.
> > +
> >  config CADENCE_QSPI
> >  	bool "Cadence QSPI driver"
> >  	help
> > diff --git a/drivers/spi/atmel_spi.c b/drivers/spi/atmel_spi.c index
> > ed6278b..db40631 100644
> > --- a/drivers/spi/atmel_spi.c
> > +++ b/drivers/spi/atmel_spi.c
> > @@ -4,6 +4,9 @@
> >   * SPDX-License-Identifier:	GPL-2.0+
> >   */
> >  #include <common.h>
> > +#include <clk.h>
> > +#include <dm.h>
> > +#include <fdtdec.h>
> >  #include <spi.h>
> >  #include <malloc.h>
> >
> > @@ -11,9 +14,15 @@
> >
> >  #include <asm/arch/clk.h>
> >  #include <asm/arch/hardware.h>
> > +#include <asm/arch/at91_spi.h>
> > +#include <asm/gpio.h>
> >
> >  #include "atmel_spi.h"
> >
> > +DECLARE_GLOBAL_DATA_PTR;
> > +
> > +#ifndef CONFIG_DM_SPI
> > +
> >  static int spi_has_wdrbt(struct atmel_spi_slave *slave)  {
> >  	unsigned int ver;
> > @@ -209,3 +218,289 @@ out:
> >
> >  	return 0;
> >  }
> > +
> > +#else
> > +
> > +#define MAX_CS_COUNT	4
> > +
> > +struct atmel_spi_platdata {
> > +	struct at91_spi *regs;
> > +};
> > +
> > +struct atmel_spi_priv {
> > +	unsigned int freq;		/* Default frequency */
> > +	unsigned int mode;
> > +	ulong bus_clk_rate;
> > +	struct gpio_desc cs_gpios[MAX_CS_COUNT]; };
> > +
> > +static int atmel_spi_claim_bus(struct udevice *dev) {
> > +	struct udevice *bus = dev_get_parent(dev);
> > +	struct atmel_spi_platdata *bus_plat = dev_get_platdata(bus);
> > +	struct atmel_spi_priv *priv = dev_get_priv(bus);
> > +	struct dm_spi_slave_platdata *slave_plat = dev_get_parent_platdata(dev);
> > +	struct at91_spi *reg_base = bus_plat->regs;
> > +	u32 cs = slave_plat->cs;
> > +	u32 freq = priv->freq;
> > +	u32 scbr, csrx, mode;
> > +
> > +	scbr = (priv->bus_clk_rate + freq - 1) / freq;
> > +	if (scbr > ATMEL_SPI_CSRx_SCBR_MAX)
> > +		return -EINVAL;
> > +
> > +	if (scbr < 1)
> > +		scbr = 1;
> > +
> > +	csrx = ATMEL_SPI_CSRx_SCBR(scbr);
> > +	csrx |= ATMEL_SPI_CSRx_BITS(ATMEL_SPI_BITS_8);
> > +
> > +	if (!(priv->mode & SPI_CPHA))
> > +		csrx |= ATMEL_SPI_CSRx_NCPHA;
> > +	if (priv->mode & SPI_CPOL)
> > +		csrx |= ATMEL_SPI_CSRx_CPOL;
> > +
> > +	writel(csrx, &reg_base->csr[cs]);
> > +
> > +	mode = ATMEL_SPI_MR_MSTR |
> > +	       ATMEL_SPI_MR_MODFDIS |
> > +	       ATMEL_SPI_MR_WDRBT |
> > +	       ATMEL_SPI_MR_PCS(~(1 << cs));
> > +
> > +	writel(mode, &reg_base->mr);
> > +
> > +	writel(ATMEL_SPI_CR_SPIEN, &reg_base->cr);
> > +
> > +	return 0;
> > +}
> > +
> > +static int atmel_spi_release_bus(struct udevice *dev) {
> > +	struct udevice *bus = dev_get_parent(dev);
> > +	struct atmel_spi_platdata *bus_plat = dev_get_platdata(bus);
> > +
> > +	writel(ATMEL_SPI_CR_SPIDIS, &bus_plat->regs->cr);
> > +
> > +	return 0;
> > +}
> > +
> > +static void atmel_spi_cs_activate(struct udevice *dev) {
> > +	struct udevice *bus = dev_get_parent(dev);
> > +	struct atmel_spi_priv *priv = dev_get_priv(bus);
> > +	struct dm_spi_slave_platdata *slave_plat = dev_get_parent_platdata(dev);
> > +	u32 cs = slave_plat->cs;
> > +
> > +	dm_gpio_set_value(&priv->cs_gpios[cs], 0); }
> > +
> > +static void atmel_spi_cs_deactivate(struct udevice *dev) {
> > +	struct udevice *bus = dev_get_parent(dev);
> > +	struct atmel_spi_priv *priv = dev_get_priv(bus);
> > +	struct dm_spi_slave_platdata *slave_plat = dev_get_parent_platdata(dev);
> > +	u32 cs = slave_plat->cs;
> > +
> > +	dm_gpio_set_value(&priv->cs_gpios[cs], 1); }
> > +
> > +static int atmel_spi_xfer(struct udevice *dev, unsigned int bitlen,
> > +			  const void *dout, void *din, unsigned long flags) {
> > +	struct udevice *bus = dev_get_parent(dev);
> > +	struct atmel_spi_platdata *bus_plat = dev_get_platdata(bus);
> > +	struct at91_spi *reg_base = bus_plat->regs;
> > +
> > +	u32 len_tx, len_rx, len;
> > +	u32 status;
> > +	const u8 *txp = dout;
> > +	u8 *rxp = din;
> > +	u8 value;
> > +
> > +	if (bitlen == 0)
> > +		goto out;
> > +
> > +	/*
> > +	 * The controller can do non-multiple-of-8 bit
> > +	 * transfers, but this driver currently doesn't support it.
> > +	 *
> > +	 * It's also not clear how such transfers are supposed to be
> > +	 * represented as a stream of bytes...this is a limitation of
> > +	 * the current SPI interface.
> > +	 */
> > +	if (bitlen % 8) {
> > +		/* Errors always terminate an ongoing transfer */
> > +		flags |= SPI_XFER_END;
> > +		goto out;
> > +	}
> > +
> > +	len = bitlen / 8;
> > +
> > +	/*
> > +	 * The controller can do automatic CS control, but it is
> > +	 * somewhat quirky, and it doesn't really buy us much anyway
> > +	 * in the context of U-Boot.
> > +	 */
> > +	if (flags & SPI_XFER_BEGIN) {
> > +		atmel_spi_cs_activate(dev);
> > +
> > +		/*
> > +		 * sometimes the RDR is not empty when we get here,
> > +		 * in theory that should not happen, but it DOES happen.
> > +		 * Read it here to be on the safe side.
> > +		 * That also clears the OVRES flag. Required if the
> > +		 * following loop exits due to OVRES!
> > +		 */
> > +		readl(&reg_base->rdr);
> > +	}
> > +
> > +	for (len_tx = 0, len_rx = 0; len_rx < len; ) {
> > +		status = readl(&reg_base->sr);
> > +
> > +		if (status & ATMEL_SPI_SR_OVRES)
> > +			return -1;
> > +
> > +		if ((len_tx < len) && (status & ATMEL_SPI_SR_TDRE)) {
> > +			if (txp)
> > +				value = *txp++;
> > +			else
> > +				value = 0;
> > +			writel(value, &reg_base->tdr);
> > +			len_tx++;
> > +		}
> > +
> > +		if (status & ATMEL_SPI_SR_RDRF) {
> > +			value = readl(&reg_base->rdr);
> > +			if (rxp)
> > +				*rxp++ = value;
> > +			len_rx++;
> > +		}
> > +	}
> > +
> > +out:
> > +	if (flags & SPI_XFER_END) {
> > +		/*
> > +		 * Wait until the transfer is completely done before
> > +		 * we deactivate CS.
> > +		 */
> > +		do {
> > +			status = readl(&reg_base->sr);
> > +		} while (!(status & ATMEL_SPI_SR_TXEMPTY));
> > +
> > +		atmel_spi_cs_deactivate(dev);
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static int atmel_spi_set_speed(struct udevice *bus, uint speed) {
> > +	struct atmel_spi_priv *priv = dev_get_priv(bus);
> > +
> > +	priv->freq = speed;
> > +
> > +	return 0;
> > +}
> > +
> > +static int atmel_spi_set_mode(struct udevice *bus, uint mode) {
> > +	struct atmel_spi_priv *priv = dev_get_priv(bus);
> > +
> > +	priv->mode = mode;
> > +
> > +	return 0;
> > +}
> > +
> > +static const struct dm_spi_ops atmel_spi_ops = {
> > +	.claim_bus	= atmel_spi_claim_bus,
> > +	.release_bus	= atmel_spi_release_bus,
> > +	.xfer		= atmel_spi_xfer,
> > +	.set_speed	= atmel_spi_set_speed,
> > +	.set_mode	= atmel_spi_set_mode,
> > +	/*
> > +	 * cs_info is not needed, since we require all chip selects to be
> > +	 * in the device tree explicitly
> > +	 */
> > +};
> > +
> > +static int atmel_spi_enable_clk(struct udevice *bus) {
> > +	struct atmel_spi_priv *priv = dev_get_priv(bus);
> > +	struct udevice *dev_clk;
> > +	struct clk clk;
> > +	ulong clk_rate;
> > +	int periph;
> > +	int ret;
> > +
> > +	ret = clk_get_by_index(bus, 0, &clk);
> > +	if (ret)
> > +		return -EINVAL;
> > +
> > +	periph = fdtdec_get_uint(gd->fdt_blob, clk.dev->of_offset, "reg", -1);
> > +	if (periph < 0)
> > +		return -EINVAL;
> > +
> > +	dev_clk = dev_get_parent(clk.dev);
> > +	ret = clk_request(dev_clk, &clk);
> > +	if (ret)
> > +		return ret;
> > +
> > +	clk.id = periph;
> > +	ret = clk_enable(&clk);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = clk_get_by_index(dev_clk, 0, &clk);
> > +	if (ret)
> > +		return ret;
> > +
> > +	clk_rate = clk_get_rate(&clk);
> > +	if (!clk_rate)
> > +		return -EINVAL;
> > +
> > +	priv->bus_clk_rate = clk_rate;
> > +
> > +	clk_free(&clk);
> > +
> > +	return 0;
> > +}
> > +
> > +static int atmel_spi_probe(struct udevice *bus) {
> > +	struct atmel_spi_platdata *bus_plat = dev_get_platdata(bus);
> > +	struct atmel_spi_priv *priv = dev_get_priv(bus);
> > +	int ret;
> > +
> > +	ret = atmel_spi_enable_clk(bus);
> > +	if (ret)
> > +		return ret;
> > +
> > +	bus_plat->regs = (struct at91_spi *)dev_get_addr(bus);
> > +
> > +	ret = gpio_request_list_by_name(bus, "cs-gpios", priv->cs_gpios,
> > +					ARRAY_SIZE(priv->cs_gpios), 0);
> > +	if (ret < 0) {
> > +		error("Can't get %s gpios! Error: %d", bus->name, ret);
> > +		return ret;
> > +	}
> > +
> > +	writel(ATMEL_SPI_CR_SWRST, &bus_plat->regs->cr);
> > +
> > +	return 0;
> > +}
> > +
> > +static const struct udevice_id atmel_spi_ids[] = {
> > +	{ .compatible = "atmel,at91rm9200-spi" },
> > +	{ }
> > +};
> > +
> > +U_BOOT_DRIVER(atmel_spi) = {
> > +	.name	= "atmel_spi",
> > +	.id	= UCLASS_SPI,
> > +	.of_match = atmel_spi_ids,
> > +	.ops	= &atmel_spi_ops,
> > +	.platdata_auto_alloc_size = sizeof(struct atmel_spi_platdata),
> > +	.priv_auto_alloc_size = sizeof(struct atmel_spi_priv),
> > +	.probe	= atmel_spi_probe,
> > +};
> > +#endif
> >


Best Regards,
Wenyou Yang


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