Re: [PATCH 2/2] spi: Add Qualcomm QUP SPI controller support
From: Andy Gross
Date: Fri Feb 07 2014 - 02:40:12 EST
On Thu, Feb 06, 2014 at 06:57:48PM +0200, Ivan T. Ivanov wrote:
> From: "Ivan T. Ivanov" <iivanov@xxxxxxxxxx>
>
> Qualcomm Universal Peripheral (QUP) core is an AHB slave that
> provides a common data path (an output FIFO and an input FIFO)
> for serial peripheral interface (SPI) mini-core. SPI in master mode
> support up to 50MHz, up to four chip selects, and a programmable
> data path from 4 bits to 32 bits; MODE0..3 protocols
>
> Signed-off-by: Ivan T. Ivanov <iivanov@xxxxxxxxxx>
> Cc: Alok Chauhan <alokc@xxxxxxxxxxxxxx>
> Cc: Gilad Avidov <gavidov@xxxxxxxxxxxxxx>
> Cc: Kiran Gunda <kgunda@xxxxxxxxxxxxxx>
> Cc: Sagar Dharia <sdharia@xxxxxxxxxxxxxx>
> ---
> drivers/spi/Kconfig | 14 +
> drivers/spi/Makefile | 1 +
> drivers/spi/spi-qup.c | 898 +++++++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 913 insertions(+)
> create mode 100644 drivers/spi/spi-qup.c
>
> diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
> index ba9310b..bf8ce6b 100644
> --- a/drivers/spi/Kconfig
> +++ b/drivers/spi/Kconfig
> @@ -381,6 +381,20 @@ config SPI_RSPI
> help
> SPI driver for Renesas RSPI blocks.
>
> +config SPI_QUP
> + tristate "Qualcomm SPI Support with QUP interface"
> + depends on ARCH_MSM
I'd change to ARCH_MSM_DT. This ensures the OF component is there.
> + help
> + Qualcomm Universal Peripheral (QUP) core is an AHB slave that
> + provides a common data path (an output FIFO and an input FIFO)
> + for serial peripheral interface (SPI) mini-core. SPI in master
> + mode support up to 50MHz, up to four chip selects, and a
> + programmable data path from 4 bits to 32 bits; supports numerous
> + protocol variants.
> +
> + This driver can also be built as a module. If so, the module
> + will be called spi_qup.
> +
> config SPI_S3C24XX
> tristate "Samsung S3C24XX series SPI"
> depends on ARCH_S3C24XX
> diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
> index 95af48d..e598147 100644
> --- a/drivers/spi/Makefile
> +++ b/drivers/spi/Makefile
> @@ -59,6 +59,7 @@ spi-pxa2xx-platform-$(CONFIG_SPI_PXA2XX_PXADMA) += spi-pxa2xx-pxadma.o
> spi-pxa2xx-platform-$(CONFIG_SPI_PXA2XX_DMA) += spi-pxa2xx-dma.o
> obj-$(CONFIG_SPI_PXA2XX) += spi-pxa2xx-platform.o
> obj-$(CONFIG_SPI_PXA2XX_PCI) += spi-pxa2xx-pci.o
> +obj-$(CONFIG_SPI_QUP) += spi-qup.o
> obj-$(CONFIG_SPI_RSPI) += spi-rspi.o
> obj-$(CONFIG_SPI_S3C24XX) += spi-s3c24xx-hw.o
> spi-s3c24xx-hw-y := spi-s3c24xx.o
> diff --git a/drivers/spi/spi-qup.c b/drivers/spi/spi-qup.c
> new file mode 100644
> index 0000000..5eb5e8f
> --- /dev/null
> +++ b/drivers/spi/spi-qup.c
> @@ -0,0 +1,898 @@
> +/*
> + * Copyright (c) 2008-2014, The Linux foundation. All rights reserved.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License rev 2 and
> + * only rev 2 as published by the free Software foundation.
> + *
> + * 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.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/err.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/list.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
Remove this for now. No runtime support.
> +#include <linux/spi/spi.h>
> +
> +#define QUP_CONFIG 0x0000
> +#define QUP_STATE 0x0004
> +#define QUP_IO_M_MODES 0x0008
> +#define QUP_SW_RESET 0x000c
> +#define QUP_OPERATIONAL 0x0018
> +#define QUP_ERROR_FLAGS 0x001c
> +#define QUP_ERROR_FLAGS_EN 0x0020
> +#define QUP_OPERATIONAL_MASK 0x0028
> +#define QUP_HW_VERSION 0x0030
> +#define QUP_MX_OUTPUT_CNT 0x0100
> +#define QUP_OUTPUT_FIFO 0x0110
> +#define QUP_MX_WRITE_CNT 0x0150
> +#define QUP_MX_INPUT_CNT 0x0200
> +#define QUP_MX_READ_CNT 0x0208
> +#define QUP_INPUT_FIFO 0x0218
> +
> +#define SPI_CONFIG 0x0300
> +#define SPI_IO_CONTROL 0x0304
> +#define SPI_ERROR_FLAGS 0x0308
> +#define SPI_ERROR_FLAGS_EN 0x030c
> +
> +/* QUP_CONFIG fields */
> +#define QUP_CONFIG_SPI_MODE (1 << 8)
> +#define QUP_CONFIG_NO_INPUT BIT(7)
> +#define QUP_CONFIG_NO_OUTPUT BIT(6)
> +#define QUP_CONFIG_N 0x001f
> +
> +/* QUP_STATE fields */
> +#define QUP_STATE_VALID BIT(2)
> +#define QUP_STATE_RESET 0
> +#define QUP_STATE_RUN 1
> +#define QUP_STATE_PAUSE 3
> +#define QUP_STATE_MASK 3
> +#define QUP_STATE_CLEAR 2
> +
> +#define QUP_HW_VERSION_2_1_1 0x20010001
> +
> +/* QUP_IO_M_MODES fields */
> +#define QUP_IO_M_PACK_EN BIT(15)
> +#define QUP_IO_M_UNPACK_EN BIT(14)
> +#define QUP_IO_M_INPUT_MODE_MASK_SHIFT 12
> +#define QUP_IO_M_OUTPUT_MODE_MASK_SHIFT 10
> +#define QUP_IO_M_INPUT_MODE_MASK (3 << QUP_IO_M_INPUT_MODE_MASK_SHIFT)
> +#define QUP_IO_M_OUTPUT_MODE_MASK (3 << QUP_IO_M_OUTPUT_MODE_MASK_SHIFT)
> +
> +#define QUP_IO_M_OUTPUT_BLOCK_SIZE(x) (((x) & (0x03 << 0)) >> 0)
> +#define QUP_IO_M_OUTPUT_FIFO_SIZE(x) (((x) & (0x07 << 2)) >> 2)
> +#define QUP_IO_M_INPUT_BLOCK_SIZE(x) (((x) & (0x03 << 5)) >> 5)
> +#define QUP_IO_M_INPUT_FIFO_SIZE(x) (((x) & (0x07 << 7)) >> 7)
> +
> +#define QUP_IO_M_MODE_FIFO 0
> +#define QUP_IO_M_MODE_BLOCK 1
> +#define QUP_IO_M_MODE_DMOV 2
> +#define QUP_IO_M_MODE_BAM 3
> +
> +/* QUP_OPERATIONAL fields */
> +#define QUP_OP_MAX_INPUT_DONE_FLAG BIT(11)
> +#define QUP_OP_MAX_OUTPUT_DONE_FLAG BIT(10)
> +#define QUP_OP_IN_SERVICE_FLAG BIT(9)
> +#define QUP_OP_OUT_SERVICE_FLAG BIT(8)
> +#define QUP_OP_IN_FIFO_FULL BIT(7)
> +#define QUP_OP_OUT_FIFO_FULL BIT(6)
> +#define QUP_OP_IN_FIFO_NOT_EMPTY BIT(5)
> +#define QUP_OP_OUT_FIFO_NOT_EMPTY BIT(4)
> +
> +/* QUP_ERROR_FLAGS and QUP_ERROR_FLAGS_EN fields */
> +#define QUP_ERROR_OUTPUT_OVER_RUN BIT(5)
> +#define QUP_ERROR_INPUT_UNDER_RUN BIT(4)
> +#define QUP_ERROR_OUTPUT_UNDER_RUN BIT(3)
> +#define QUP_ERROR_INPUT_OVER_RUN BIT(2)
> +
> +/* SPI_CONFIG fields */
> +#define SPI_CONFIG_HS_MODE BIT(10)
> +#define SPI_CONFIG_INPUT_FIRST BIT(9)
> +#define SPI_CONFIG_LOOPBACK BIT(8)
> +
> +/* SPI_IO_CONTROL fields */
> +#define SPI_IO_C_FORCE_CS BIT(11)
> +#define SPI_IO_C_CLK_IDLE_HIGH BIT(10)
> +#define SPI_IO_C_MX_CS_MODE BIT(8)
> +#define SPI_IO_C_CS_N_POLARITY_0 BIT(4)
> +#define SPI_IO_C_CS_SELECT(x) (((x) & 3) << 2)
> +#define SPI_IO_C_CS_SELECT_MASK 0x000c
> +#define SPI_IO_C_TRISTATE_CS BIT(1)
> +#define SPI_IO_C_NO_TRI_STATE BIT(0)
> +
> +/* SPI_ERROR_FLAGS and SPI_ERROR_FLAGS_EN fields */
> +#define SPI_ERROR_CLK_OVER_RUN BIT(1)
> +#define SPI_ERROR_CLK_UNDER_RUN BIT(0)
> +
> +#define SPI_NUM_CHIPSELECTS 4
> +
> +/* high speed mode is when bus rate is greater then 26MHz */
> +#define SPI_HS_MIN_RATE 26000000
> +
> +#define SPI_DELAY_THRESHOLD 1
> +#define SPI_DELAY_RETRY 10
> +
> +struct spi_qup_device {
> + int bits_per_word;
> + int chip_select;
> + int speed_hz;
> + u16 mode;
> +};
> +
> +struct spi_qup {
> + void __iomem *base;
> + struct device *dev;
> + struct clk *cclk; /* core clock */
> + struct clk *iclk; /* interface clock */
> + int irq;
> + u32 max_speed_hz;
> + u32 speed_hz;
> +
> + int in_fifo_sz;
> + int out_fifo_sz;
> + int in_blk_sz;
> + int out_blk_sz;
> +
> + struct spi_transfer *xfer;
> + struct completion done;
> + int error;
> + int bytes_per_word;
> + int tx_bytes;
> + int rx_bytes;
> +};
> +
> +
> +static inline bool spi_qup_is_valid_state(struct spi_qup *controller)
> +{
> + u32 opstate = readl_relaxed(controller->base + QUP_STATE);
> +
> + return opstate & QUP_STATE_VALID;
> +}
> +
> +static int spi_qup_set_state(struct spi_qup *controller, u32 state)
> +{
> + unsigned long loop = 0;
> + u32 cur_state;
> +
> + cur_state = readl_relaxed(controller->base + QUP_STATE);
> + /*
> + * Per spec: for PAUSE_STATE to RESET_STATE, two writes
> + * of (b10) are required
> + */
> + if (((cur_state & QUP_STATE_MASK) == QUP_STATE_PAUSE) &&
> + (state == QUP_STATE_RESET)) {
> + writel_relaxed(QUP_STATE_CLEAR, controller->base + QUP_STATE);
> + writel_relaxed(QUP_STATE_CLEAR, controller->base + QUP_STATE);
> + } else {
> + cur_state &= ~QUP_STATE_MASK;
> + cur_state |= state;
> + writel_relaxed(cur_state, controller->base + QUP_STATE);
> + }
> +
> + while (!spi_qup_is_valid_state(controller)) {
> +
> + usleep_range(SPI_DELAY_THRESHOLD, SPI_DELAY_THRESHOLD * 2);
> +
> + if (++loop > SPI_DELAY_RETRY)
> + return -EIO;
> + }
> +
> + return 0;
> +}
> +
> +static void spi_qup_deassert_cs(struct spi_qup *controller,
> + struct spi_qup_device *chip)
> +{
> + u32 iocontol, mask;
> +
> + iocontol = readl_relaxed(controller->base + SPI_IO_CONTROL);
> +
> + /* Disable auto CS toggle and use manual */
> + iocontol &= ~SPI_IO_C_MX_CS_MODE;
> + iocontol |= SPI_IO_C_FORCE_CS;
> +
> + iocontol &= ~SPI_IO_C_CS_SELECT_MASK;
> + iocontol |= SPI_IO_C_CS_SELECT(chip->chip_select);
> +
> + mask = SPI_IO_C_CS_N_POLARITY_0 << chip->chip_select;
> +
> + if (chip->mode & SPI_CS_HIGH)
> + iocontol &= ~mask;
> + else
> + iocontol |= mask;
> +
> + writel_relaxed(iocontol, controller->base + SPI_IO_CONTROL);
> +}
> +
> +static void spi_qup_assert_cs(struct spi_qup *controller,
> + struct spi_qup_device *chip)
> +{
> + u32 iocontol, mask;
> +
> + iocontol = readl_relaxed(controller->base + SPI_IO_CONTROL);
> +
> + /* Disable auto CS toggle and use manual */
> + iocontol &= ~SPI_IO_C_MX_CS_MODE;
> + iocontol |= SPI_IO_C_FORCE_CS;
> +
> + iocontol &= ~SPI_IO_C_CS_SELECT_MASK;
> + iocontol |= SPI_IO_C_CS_SELECT(chip->chip_select);
> +
> + mask = SPI_IO_C_CS_N_POLARITY_0 << chip->chip_select;
> +
> + if (chip->mode & SPI_CS_HIGH)
> + iocontol |= mask;
> + else
> + iocontol &= ~mask;
> +
> + writel_relaxed(iocontol, controller->base + SPI_IO_CONTROL);
> +}
> +
> +static void spi_qup_fifo_read(struct spi_qup *controller,
> + struct spi_transfer *xfer)
> +{
> + u8 *rx_buf = xfer->rx_buf;
> + u32 word, state;
> + int idx, shift;
> +
> + while (controller->rx_bytes < xfer->len) {
> +
> + state = readl_relaxed(controller->base + QUP_OPERATIONAL);
> + if (0 == (state & QUP_OP_IN_FIFO_NOT_EMPTY))
> + break;
> +
> + word = readl_relaxed(controller->base + QUP_INPUT_FIFO);
> +
> + for (idx = 0; idx < controller->bytes_per_word &&
> + controller->rx_bytes < xfer->len; idx++,
> + controller->rx_bytes++) {
> +
> + if (!rx_buf)
> + continue;
> + /*
> + * The data format depends on bytes_per_word:
> + * 4 bytes: 0x12345678
> + * 2 bytes: 0x00001234
> + * 1 byte : 0x00000012
> + */
> + shift = BITS_PER_BYTE;
> + shift *= (controller->bytes_per_word - idx - 1);
> + rx_buf[controller->rx_bytes] = word >> shift;
> + }
> + }
> +}
> +
> +static void spi_qup_fifo_write(struct spi_qup *controller,
> + struct spi_transfer *xfer)
> +{
> + const u8 *tx_buf = xfer->tx_buf;
> + u32 word, state, data;
> + int idx;
> +
> + while (controller->tx_bytes < xfer->len) {
> +
> + state = readl_relaxed(controller->base + QUP_OPERATIONAL);
> + if (state & QUP_OP_OUT_FIFO_FULL)
> + break;
> +
> + word = 0;
> + for (idx = 0; idx < controller->bytes_per_word &&
> + controller->tx_bytes < xfer->len; idx++,
> + controller->tx_bytes++) {
> +
> + if (!tx_buf)
> + continue;
> +
> + data = tx_buf[controller->tx_bytes];
> + word |= data << (BITS_PER_BYTE * (3 - idx));
> + }
> +
> + writel_relaxed(word, controller->base + QUP_OUTPUT_FIFO);
> + }
> +}
> +
> +static irqreturn_t spi_qup_qup_irq(int irq, void *dev_id)
> +{
> + struct spi_qup *controller = dev_id;
> + struct spi_transfer *xfer;
> + u32 opflags, qup_err, spi_err;
> +
> + xfer = controller->xfer;
> +
> + qup_err = readl_relaxed(controller->base + QUP_ERROR_FLAGS);
> + spi_err = readl_relaxed(controller->base + SPI_ERROR_FLAGS);
> + opflags = readl_relaxed(controller->base + QUP_OPERATIONAL);
> +
> + writel_relaxed(qup_err, controller->base + QUP_ERROR_FLAGS);
> + writel_relaxed(spi_err, controller->base + SPI_ERROR_FLAGS);
> + writel_relaxed(opflags, controller->base + QUP_OPERATIONAL);
> +
> + if (!xfer)
> + return IRQ_HANDLED;
> +
> + if (qup_err) {
> + if (qup_err & QUP_ERROR_OUTPUT_OVER_RUN)
> + dev_warn(controller->dev, "OUTPUT_OVER_RUN\n");
> + if (qup_err & QUP_ERROR_INPUT_UNDER_RUN)
> + dev_warn(controller->dev, "INPUT_UNDER_RUN\n");
> + if (qup_err & QUP_ERROR_OUTPUT_UNDER_RUN)
> + dev_warn(controller->dev, "OUTPUT_UNDER_RUN\n");
> + if (qup_err & QUP_ERROR_INPUT_OVER_RUN)
> + dev_warn(controller->dev, "INPUT_OVER_RUN\n");
> +
> + controller->error = -EIO;
> + }
> +
> + if (spi_err) {
> + if (spi_err & SPI_ERROR_CLK_OVER_RUN)
> + dev_warn(controller->dev, "CLK_OVER_RUN\n");
> + if (spi_err & SPI_ERROR_CLK_UNDER_RUN)
> + dev_warn(controller->dev, "CLK_UNDER_RUN\n");
> +
> + controller->error = -EIO;
> + }
> +
> + if (opflags & QUP_OP_IN_SERVICE_FLAG) {
> + writel_relaxed(QUP_OP_IN_SERVICE_FLAG,
> + controller->base + QUP_OPERATIONAL);
> + spi_qup_fifo_read(controller, xfer);
> + }
> +
> + if (opflags & QUP_OP_OUT_SERVICE_FLAG) {
> + writel_relaxed(QUP_OP_OUT_SERVICE_FLAG,
> + controller->base + QUP_OPERATIONAL);
> + spi_qup_fifo_write(controller, xfer);
> + }
> +
> + if (controller->rx_bytes == xfer->len ||
> + controller->error)
> + complete(&controller->done);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int spi_qup_transfer_do(struct spi_qup *controller,
> + struct spi_qup_device *chip,
> + struct spi_transfer *xfer)
> +{
> + unsigned long timeout;
> + int ret = -EIO;
> +
> + reinit_completion(&controller->done);
> +
> + timeout = DIV_ROUND_UP(controller->speed_hz, MSEC_PER_SEC);
> + timeout = DIV_ROUND_UP(xfer->len * 8, timeout);
> + timeout = 100 * msecs_to_jiffies(timeout);
> +
> + controller->rx_bytes = 0;
> + controller->tx_bytes = 0;
> + controller->error = 0;
> + controller->xfer = xfer;
> +
> + if (spi_qup_set_state(controller, QUP_STATE_RUN)) {
> + dev_warn(controller->dev, "cannot set RUN state\n");
> + goto exit;
> + }
> +
> + if (spi_qup_set_state(controller, QUP_STATE_PAUSE)) {
> + dev_warn(controller->dev, "cannot set PAUSE state\n");
> + goto exit;
> + }
> +
> + spi_qup_fifo_write(controller, xfer);
> +
> + if (spi_qup_set_state(controller, QUP_STATE_RUN)) {
> + dev_warn(controller->dev, "cannot set EXECUTE state\n");
> + goto exit;
> + }
> +
> + if (!wait_for_completion_timeout(&controller->done, timeout))
> + ret = -ETIMEDOUT;
> + else
> + ret = controller->error;
> +exit:
> + controller->xfer = NULL;
Should the manipulation of controller->xfer be protected by spinlock?
> + controller->error = 0;
> + controller->rx_bytes = 0;
> + controller->tx_bytes = 0;
> + spi_qup_set_state(controller, QUP_STATE_RESET);
> + return ret;
> +}
> +
> +static int spi_qup_setup(struct spi_device *spi)
> +{
> + struct spi_qup *controller = spi_master_get_devdata(spi->master);
> + struct spi_qup_device *chip = spi_get_ctldata(spi);
> +
> + if (spi->chip_select >= spi->master->num_chipselect) {
> + dev_err(controller->dev, "invalid chip_select %d\n",
> + spi->chip_select);
> + return -EINVAL;
> + }
> +
> + if (spi->max_speed_hz > controller->max_speed_hz) {
> + dev_err(controller->dev, "invalid max_speed_hz %d\n",
> + spi->max_speed_hz);
> + return -EINVAL;
> + }
> +
> + if (!chip) {
> + /* First setup */
> + chip = kzalloc(sizeof(*chip), GFP_KERNEL);
> + if (!chip) {
> + dev_err(controller->dev, "no memory for chip data\n");
> + return -ENOMEM;
> + }
> +
> + spi_set_ctldata(spi, chip);
> + }
> +
> + return 0;
> +}
> +
> +static void spi_qup_cleanup(struct spi_device *spi)
> +{
> + struct spi_qup_device *chip = spi_get_ctldata(spi);
> +
> + if (!chip)
> + return;
> +
> + spi_set_ctldata(spi, NULL);
> + kfree(chip);
> +}
> +
> +/* set clock freq, clock ramp, bits per work */
> +static int spi_qup_io_setup(struct spi_device *spi,
> + struct spi_transfer *xfer)
> +{
> + struct spi_qup *controller = spi_master_get_devdata(spi->master);
> + struct spi_qup_device *chip = spi_get_ctldata(spi);
> + u32 iocontol, config, iomode, mode;
> + int ret, n_words;
> +
> + if (spi->mode & SPI_LOOP && xfer->len > controller->in_fifo_sz) {
> + dev_err(controller->dev, "too big size for loopback %d > %d\n",
> + xfer->len, controller->in_fifo_sz);
> + return -EIO;
> + }
> +
> + chip->mode = spi->mode;
> + chip->speed_hz = spi->max_speed_hz;
> + if (xfer->speed_hz)
> + chip->speed_hz = xfer->speed_hz;
> +
> + if (controller->speed_hz != chip->speed_hz) {
> + ret = clk_set_rate(controller->cclk, chip->speed_hz);
> + if (ret) {
> + dev_err(controller->dev, "fail to set frequency %d",
> + chip->speed_hz);
> + return -EIO;
> + }
> + }
> +
> + controller->speed_hz = chip->speed_hz;
> +
> + chip->bits_per_word = spi->bits_per_word;
> + if (xfer->bits_per_word)
> + chip->bits_per_word = xfer->bits_per_word;
> +
> + if (chip->bits_per_word <= 8)
> + controller->bytes_per_word = 1;
> + else if (chip->bits_per_word <= 16)
> + controller->bytes_per_word = 2;
> + else
> + controller->bytes_per_word = 4;
> +
> + if (controller->bytes_per_word > xfer->len ||
> + xfer->len % controller->bytes_per_word != 0){
> + /* No partial transfers */
> + dev_err(controller->dev, "invalid len %d for %d bits\n",
> + xfer->len, chip->bits_per_word);
> + return -EIO;
> + }
> +
> + n_words = xfer->len / controller->bytes_per_word;
> +
> + if (spi_qup_set_state(controller, QUP_STATE_RESET)) {
> + dev_err(controller->dev, "cannot set RESET state\n");
> + return -EIO;
> + }
> +
> + if (n_words <= controller->in_fifo_sz) {
> + mode = QUP_IO_M_MODE_FIFO;
> + writel_relaxed(n_words, controller->base + QUP_MX_READ_CNT);
> + writel_relaxed(n_words, controller->base + QUP_MX_WRITE_CNT);
> + /* must be zero for FIFO */
> + writel_relaxed(0, controller->base + QUP_MX_INPUT_CNT);
> + writel_relaxed(0, controller->base + QUP_MX_OUTPUT_CNT);
> + } else {
> + mode = QUP_IO_M_MODE_BLOCK;
> + writel_relaxed(n_words, controller->base + QUP_MX_INPUT_CNT);
> + writel_relaxed(n_words, controller->base + QUP_MX_OUTPUT_CNT);
> + /* must be zero for BLOCK and BAM */
> + writel_relaxed(0, controller->base + QUP_MX_READ_CNT);
> + writel_relaxed(0, controller->base + QUP_MX_WRITE_CNT);
> + }
> +
> + iomode = readl_relaxed(controller->base + QUP_IO_M_MODES);
> + /* Set input and output transfer mode */
> + iomode &= ~(QUP_IO_M_INPUT_MODE_MASK | QUP_IO_M_OUTPUT_MODE_MASK);
> + iomode &= ~(QUP_IO_M_PACK_EN | QUP_IO_M_UNPACK_EN);
> + iomode |= (mode << QUP_IO_M_OUTPUT_MODE_MASK_SHIFT);
> + iomode |= (mode << QUP_IO_M_INPUT_MODE_MASK_SHIFT);
> +
> + writel_relaxed(iomode, controller->base + QUP_IO_M_MODES);
> +
> + config = readl_relaxed(controller->base + SPI_CONFIG);
> +
> + if (chip->mode & SPI_LOOP)
> + config |= SPI_CONFIG_LOOPBACK;
> + else
> + config &= ~SPI_CONFIG_LOOPBACK;
> +
> + if (chip->mode & SPI_CPHA)
> + config &= ~SPI_CONFIG_INPUT_FIRST;
> + else
> + config |= SPI_CONFIG_INPUT_FIRST;
> +
> + /*
> + * HS_MODE improves signal stability for spi-clk high rates
> + * but is invalid in loop back mode.
> + */
> + if ((controller->speed_hz >= SPI_HS_MIN_RATE) &&
> + !(chip->mode & SPI_LOOP))
> + config |= SPI_CONFIG_HS_MODE;
> + else
> + config &= ~SPI_CONFIG_HS_MODE;
> +
> + writel_relaxed(config, controller->base + SPI_CONFIG);
> +
> + config = readl_relaxed(controller->base + QUP_CONFIG);
> + config &= ~(QUP_CONFIG_NO_INPUT | QUP_CONFIG_NO_OUTPUT | QUP_CONFIG_N);
> + config |= chip->bits_per_word - 1;
> + config |= QUP_CONFIG_SPI_MODE;
> + writel_relaxed(config, controller->base + QUP_CONFIG);
> +
> + iocontol = readl_relaxed(controller->base + SPI_IO_CONTROL);
> +
> + /* Disable auto CS toggle */
> + iocontol &= ~SPI_IO_C_MX_CS_MODE;
> +
> + if (chip->mode & SPI_CPOL)
> + iocontol |= SPI_IO_C_CLK_IDLE_HIGH;
> + else
> + iocontol &= ~SPI_IO_C_CLK_IDLE_HIGH;
> +
> + writel_relaxed(iocontol, controller->base + SPI_IO_CONTROL);
> +
> + /*
> + * TODO: In BAM mode mask INPUT and OUTPUT service flags in
> + * to prevent IRQs on FIFO status change.
> + */
Remove the TODO. Not necessary. This stuff can be added when it becomes BAM
enabled.
> + writel_relaxed(0, controller->base + QUP_OPERATIONAL_MASK);
> +
> + return 0;
> +}
> +
> +static int spi_qup_transfer_one(struct spi_master *master,
> + struct spi_message *msg)
> +{
> + struct spi_qup *controller = spi_master_get_devdata(master);
> + struct spi_qup_device *chip = spi_get_ctldata(msg->spi);
> + struct spi_transfer *xfer;
> + struct spi_device *spi;
> + unsigned cs_change;
> + int status;
> +
> + spi = msg->spi;
> + cs_change = 1;
> + status = 0;
> +
> + list_for_each_entry(xfer, &msg->transfers, transfer_list) {
> +
> + status = spi_qup_io_setup(spi, xfer);
> + if (status)
> + break;
> +
no locking? This whole code block needs to have some type of mutex_lock to keep
others from trouncing the hardware while you are doing this transfer.
> + if (cs_change)
> + spi_qup_assert_cs(controller, chip);
Should the CS be done outside the loop? I'd expect the following sequence to
happen:
- change CS
- Loop and do some transfers
- deassert CS
In this code, you reinitialize and assert/deassert CS for every transaction.
> +
> + cs_change = xfer->cs_change;
> +
> + /* Do actual transfer */
> + status = spi_qup_transfer_do(controller, chip, xfer);
> + if (status)
> + break;
> +
> + msg->actual_length += xfer->len;
> +
> + if (xfer->delay_usecs)
> + udelay(xfer->delay_usecs);
> +
> + if (cs_change)
> + spi_qup_deassert_cs(controller, chip);
> + }
> +
> + if (status || !cs_change)
> + spi_qup_deassert_cs(controller, chip);
> +
> + msg->status = status;
> + spi_finalize_current_message(master);
> + return status;
> +}
> +
> +static int spi_qup_probe(struct platform_device *pdev)
> +{
> + struct spi_master *master;
> + struct clk *iclk, *cclk;
> + struct spi_qup *controller;
> + struct resource *res;
> + struct device *dev;
> + void __iomem *base;
> + u32 data, max_freq, iomode;
> + int ret, irq, size;
> +
> + dev = &pdev->dev;
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + base = devm_ioremap_resource(dev, res);
> + if (IS_ERR(base))
> + return PTR_ERR(base);
> +
> + irq = platform_get_irq(pdev, 0);
> +
> + if (irq < 0)
> + return irq;
> +
> + cclk = devm_clk_get(dev, "core");
> + if (IS_ERR(cclk)) {
> + dev_err(dev, "cannot get core clock\n");
No need to error print. devm_clk_get already outputs something
> + return PTR_ERR(cclk);
> + }
> +
> + iclk = devm_clk_get(dev, "iface");
> + if (IS_ERR(iclk)) {
> + dev_err(dev, "cannot get iface clock\n");
No need to error print. devm_clk_get already outputs something
> + return PTR_ERR(iclk);
> + }
> +
> + if (of_property_read_u32(dev->of_node, "spi-max-frequency", &max_freq))
> + max_freq = 19200000;
I'd set the default to 50MHz as that is the max supported by hardware. I'd just
set max_freq declaration to 50MHz and then check the value if it is changed via
DT.
> +
> + if (!max_freq) {
> + dev_err(dev, "invalid clock frequency %d\n", max_freq);
> + return -ENXIO;
> + }
This is buggy. Remove this and collapse into the of_property_read_u32 if
statement. On non-zero, check the range for validity.
> +
> + ret = clk_set_rate(cclk, max_freq);
> + if (ret)
> + dev_warn(dev, "fail to set SPI frequency %d\n", max_freq);
Bail here?
> +
> + ret = clk_prepare_enable(cclk);
> + if (ret) {
> + dev_err(dev, "cannot enable core clock\n");
> + return ret;
> + }
> +
> + ret = clk_prepare_enable(iclk);
> + if (ret) {
> + clk_disable_unprepare(cclk);
> + dev_err(dev, "cannot enable iface clock\n");
> + return ret;
> + }
> +
> + data = readl_relaxed(base + QUP_HW_VERSION);
> +
> + if (data < QUP_HW_VERSION_2_1_1) {
> + clk_disable_unprepare(cclk);
> + clk_disable_unprepare(iclk);
> + dev_err(dev, "v.%08x is not supported\n", data);
> + return -ENXIO;
> + }
> +
> + master = spi_alloc_master(dev, sizeof(struct spi_qup));
> + if (!master) {
> + clk_disable_unprepare(cclk);
> + clk_disable_unprepare(iclk);
> + dev_err(dev, "cannot allocate master\n");
> + return -ENOMEM;
> + }
> +
> + master->bus_num = pdev->id;
> + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
> + master->num_chipselect = SPI_NUM_CHIPSELECTS;
> + master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
> + master->setup = spi_qup_setup;
> + master->cleanup = spi_qup_cleanup;
> + master->transfer_one_message = spi_qup_transfer_one;
> + master->dev.of_node = pdev->dev.of_node;
> + master->auto_runtime_pm = true;
Remove this. No runtime support
> +
> + platform_set_drvdata(pdev, master);
> +
> + controller = spi_master_get_devdata(master);
> +
> + controller->dev = dev;
> + controller->base = base;
> + controller->iclk = iclk;
> + controller->cclk = cclk;
> + controller->irq = irq;
> + controller->max_speed_hz = clk_get_rate(cclk);
> + controller->speed_hz = controller->max_speed_hz;
> +
> + init_completion(&controller->done);
> +
> + iomode = readl_relaxed(base + QUP_IO_M_MODES);
> +
> + size = QUP_IO_M_OUTPUT_BLOCK_SIZE(iomode);
> + if (size)
> + controller->out_blk_sz = size * 16;
> + else
> + controller->out_blk_sz = 4;
> +
> + size = QUP_IO_M_INPUT_BLOCK_SIZE(iomode);
> + if (size)
> + controller->in_blk_sz = size * 16;
> + else
> + controller->in_blk_sz = 4;
> +
> + size = QUP_IO_M_OUTPUT_FIFO_SIZE(iomode);
> + controller->out_fifo_sz = controller->out_blk_sz * (2 << size);
> +
> + size = QUP_IO_M_INPUT_FIFO_SIZE(iomode);
> + controller->in_fifo_sz = controller->in_blk_sz * (2 << size);
> +
> + dev_info(dev, "v.%08x IN:block:%d, fifo:%d, OUT:block:%d, fifo:%d\n",
> + data, controller->in_blk_sz, controller->in_fifo_sz,
> + controller->out_blk_sz, controller->out_fifo_sz);
> +
> + writel_relaxed(1, base + QUP_SW_RESET);
> +
> + ret = spi_qup_set_state(controller, QUP_STATE_RESET);
> + if (ret) {
> + dev_err(dev, "cannot set RESET state\n");
> + goto error;
> + }
> +
> + writel_relaxed(0, base + QUP_OPERATIONAL);
> + writel_relaxed(0, base + QUP_IO_M_MODES);
> + writel_relaxed(0, base + QUP_OPERATIONAL_MASK);
> + writel_relaxed(SPI_ERROR_CLK_UNDER_RUN | SPI_ERROR_CLK_OVER_RUN,
> + base + SPI_ERROR_FLAGS_EN);
> +
> + writel_relaxed(0, base + SPI_CONFIG);
> + writel_relaxed(SPI_IO_C_NO_TRI_STATE, base + SPI_IO_CONTROL);
> +
> + ret = devm_request_irq(dev, irq, spi_qup_qup_irq,
> + IRQF_TRIGGER_HIGH, pdev->name, controller);
> + if (ret) {
> + dev_err(dev, "cannot request IRQ %d\n", irq);
unnecessary print
> + goto error;
> + }
> +
> + ret = devm_spi_register_master(dev, master);
> + if (!ret) {
> + pm_runtime_set_autosuspend_delay(dev, MSEC_PER_SEC);
> + pm_runtime_use_autosuspend(dev);
> + pm_runtime_set_active(dev);
> + pm_runtime_enable(dev);
Remove all the runtime stuff. not supported right now.
> + return ret;
> + }
> +error:
> + clk_disable_unprepare(cclk);
> + clk_disable_unprepare(iclk);
> + spi_master_put(master);
> + return ret;
> +}
> +
> +#ifdef CONFIG_PM_RUNTIME
Remove all the runtime stuff. not supported right now.
> +static int spi_qup_pm_suspend_runtime(struct device *device)
> +{
> + struct spi_master *master = dev_get_drvdata(device);
> + struct spi_qup *controller = spi_master_get_devdata(master);
> +
> + disable_irq(controller->irq);
> + clk_disable_unprepare(controller->cclk);
> + clk_disable_unprepare(controller->iclk);
> + dev_dbg(device, "suspend runtime\n");
> + return 0;
> +}
> +
> +static int spi_qup_pm_resume_runtime(struct device *device)
> +{
> + struct spi_master *master = dev_get_drvdata(device);
> + struct spi_qup *controller = spi_master_get_devdata(master);
> +
> + clk_prepare_enable(controller->cclk);
> + clk_prepare_enable(controller->iclk);
> + enable_irq(controller->irq);
> + dev_dbg(device, "resume runtime\n");
> + return 0;
> +}
> +#endif /* CONFIG_PM_RUNTIME */
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int spi_qup_suspend(struct device *device)
> +{
> + struct spi_master *master = dev_get_drvdata(device);
> + struct spi_qup *controller = spi_master_get_devdata(master);
> + int status;
> +
> + status = spi_master_suspend(master);
> + if (!status) {
> + disable_irq(controller->irq);
> + clk_disable_unprepare(controller->cclk);
> + clk_disable_unprepare(controller->iclk);
> + }
> +
> + dev_dbg(device, "system suspend %d\n", status);
> + return status;
> +}
Remove all the suspend/resume stuff. not supported right now.
> +
> +static int spi_qup_resume(struct device *device)
> +{
> + struct spi_master *master = dev_get_drvdata(device);
> + struct spi_qup *controller = spi_master_get_devdata(master);
> + int status;
> +
> + clk_prepare_enable(controller->cclk);
> + clk_prepare_enable(controller->iclk);
> +
> + status = spi_master_resume(master);
> +
> + dev_dbg(device, "system resume %d\n", status);
> + return status;
> +}
> +#endif /* CONFIG_PM_SLEEP */
Remove all the suspend/resume stuff. not supported right now.
> +
> +static int spi_qup_remove(struct platform_device *pdev)
> +{
> + struct spi_master *master = dev_get_drvdata(&pdev->dev);
> + struct spi_qup *controller = spi_master_get_devdata(master);
> +
> + pm_runtime_get_sync(&pdev->dev);
> +
Do we need to wait for any current transactions to complete
and do a devm_free_irq()?
> + clk_disable_unprepare(controller->cclk);
> + clk_disable_unprepare(controller->iclk);
> +
> + pm_runtime_put_noidle(&pdev->dev);
> + pm_runtime_disable(&pdev->dev);
> + return 0;
> +}
> +
> +static struct of_device_id spi_qup_dt_match[] = {
> + { .compatible = "qcom,spi-qup-v2", },
Need compatible tags of qcom,spi-qup-v2.1.1 (msm8974 v1) or qcom,spi-qup-v2.2.1
(msm8974 v2)
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, spi_qup_dt_match);
> +
> +static const struct dev_pm_ops spi_qup_dev_pm_ops = {
> + SET_SYSTEM_SLEEP_PM_OPS(spi_qup_suspend, spi_qup_resume)
> + SET_RUNTIME_PM_OPS(spi_qup_pm_suspend_runtime,
> + spi_qup_pm_resume_runtime,
> + NULL)
> +};
Remove this for now.
> +
> +static struct platform_driver spi_qup_driver = {
> + .driver = {
> + .name = "spi_qup",
> + .owner = THIS_MODULE,
> + .pm = &spi_qup_dev_pm_ops,
> + .of_match_table = spi_qup_dt_match,
> + },
> + .probe = spi_qup_probe,
> + .remove = spi_qup_remove,
> +};
> +module_platform_driver(spi_qup_driver);
> +
> +MODULE_LICENSE("GPL v2");
> +MODULE_VERSION("0.4");
> +MODULE_ALIAS("platform:spi_qup");
> --
> 1.7.9.5
>
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