On 13.01.2012 11:48, Stefano Babic wrote:
On 12/01/2012 16:27, Dirk Behme wrote:
From: Eric Nelson eric.nelson@boundarydevices.com
Signed-off-by: Eric Nelson eric.nelson@boundarydevices.com CC: Jason Liu jason.hui@linaro.org CC: Stefano Babic sbabic@denx.de
drivers/spi/Makefile | 1 + drivers/spi/imx_ecspi.c | 334 +++++++++++++++++++++++++++++++++++++++++++++++ include/imx_spi.h | 97 ++++++++++++++ 3 files changed, 432 insertions(+), 0 deletions(-) create mode 100644 drivers/spi/imx_ecspi.c create mode 100644 include/imx_spi.h
Hi Dirk,
before digging too deep inside the driver: I do not see any apoparent reason why we must add a separate driver instead of adapting what we currently have. And most part are quite identical to drivers/spi/mxc_spi.c. We should change mxc_spi.c for the imx6 relevant parts, instead of adding a new copy.
new file mode 100644 index 0000000..1468208 --- /dev/null +++ b/drivers/spi/imx_ecspi.c @@ -0,0 +1,334 @@ +/*
- (C) Copyright 2008-2010 Freescale Semiconductor, Inc.
- See file CREDITS for list of people who contributed to this
- project.
- This program is free software; you can redistribute it and/or
- modify it under the terms of the GNU General Public License as
- published by the Free Software Foundation; either version 2 of
- the License, or (at your option) any later version.
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place, Suite 330, Boston,
- MA 02111-1307 USA
- */
+#include <config.h> +#include <common.h> +#include <spi.h> +#include <asm/errno.h> +#include <linux/types.h> +#include <asm/io.h> +#include <malloc.h> +#include <asm/arch/clock.h> +#include <imx_spi.h>
+static inline struct imx_spi_dev_t *to_imx_spi_slave(struct spi_slave *slave) +{
- return container_of(slave, struct imx_spi_dev_t, slave);
+}
+static s32 spi_reset(struct spi_slave *slave) +{
- u32 clk_src = mxc_get_clock(MXC_CSPI_CLK);
- u32 pre_div = 0, post_div = 0, reg_ctrl, reg_config;
- struct imx_spi_dev_t *dev = to_imx_spi_slave(slave);
- struct spi_reg_t *reg = &(dev->reg);
- if (dev->freq == 0) {
printf("Error: desired clock is 0\n");return 1;- }
- reg_ctrl = readl(dev->base + SPI_CON_REG);
- reg_config = readl(dev->base + SPI_CFG_REG);
- /* Reset spi */
The functiion reassembles spi_cfg_mxc in mxc_spi.c, usinf fixed offset instead of structures.
+/*
- SPI xchg
- */
+int spi_xchg_single(struct spi_slave *slave, unsigned int bitlen,
- const u8 *dout, u8 *din, unsigned long flags)
+{
- int nbytes = (bitlen + 7) / 8;
- struct imx_spi_dev_t *dev = to_imx_spi_slave(slave);
- struct spi_reg_t *spi_reg = &(dev->reg);
- u32 loop_cnt ;
- if (!slave)
return -1;- if (spi_reg->ctrl_reg == 0) {
printf("Error: spi(base=0x%x) has not been initialized yet\n",dev->base);return -1;- }
- spi_reg->ctrl_reg = (spi_reg->ctrl_reg & ~0xFFF00000) | \
((bitlen - 1) << 20);- writel(spi_reg->ctrl_reg, dev->base + SPI_CON_REG);
- writel(spi_reg->cfg_reg, dev->base + SPI_CFG_REG);
- /* move data to the tx fifo */
- debug("dout=0x%p, bitlen=%x\n", dout, bitlen);
- /*
* The SPI controller works only with words,* check if less than a word is sent.* Access to the FIFO is only 32 bit*/- if (bitlen % 32) {
u32 data = 0;I see no specific i.MX6 code here, and the function is not very different as spi_xchg_single(). Really I do not think we can add a copy of the already provided driver, sorry.
Yes, understood, see
http://lists.denx.de/pipermail/u-boot/2012-January/115611.html
Let's have Eric a look to this.
Anyway, many thanks for looking at it,
Dirk