2014-02-13 16:23:13

by Ivan T. Ivanov

[permalink] [raw]
Subject: [PATH v2 2/2] spi: Add Qualcomm QUP SPI controller support

From: "Ivan T. Ivanov" <[email protected]>

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 supports up to 50MHz, up to four chip selects, programmable
data path from 4 bits to 32 bits and numerous protocol variants.

Cc: Alok Chauhan <[email protected]>
Cc: Gilad Avidov <[email protected]>
Cc: Kiran Gunda <[email protected]>
Cc: Sagar Dharia <[email protected]>
Cc: [email protected]
Signed-off-by: Ivan T. Ivanov <[email protected]>
---
drivers/spi/Kconfig | 13 +
drivers/spi/Makefile | 1 +
drivers/spi/spi-qup.c | 837 +++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 851 insertions(+)
create mode 100644 drivers/spi/spi-qup.c

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index ba9310b..86c254d 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -381,6 +381,19 @@ config SPI_RSPI
help
SPI driver for Renesas RSPI blocks.

+config SPI_QUP
+ tristate "Qualcomm SPI controller with QUP interface"
+ depends on ARCH_MSM_DT
+ 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 supports up to 50MHz, up to four chip selects, programmable
+ data path from 4 bits to 32 bits and 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..b0bcc09
--- /dev/null
+++ b/drivers/spi/spi-qup.c
@@ -0,0 +1,837 @@
+/*
+ * 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>
+#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_CLOCK_AUTO_GATE BIT(13)
+#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_MAX_RATE 50000000
+
+#define SPI_DELAY_THRESHOLD 1
+#define SPI_DELAY_RETRY 10
+
+struct spi_qup_device {
+ int select;
+ 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;
+ spinlock_t lock;
+
+ 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 w_size; /* bytes per SPI 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;
+ u32 cur_state;
+
+ loop = 0;
+ while (!spi_qup_is_valid_state(controller)) {
+
+ usleep_range(SPI_DELAY_THRESHOLD, SPI_DELAY_THRESHOLD * 2);
+
+ if (++loop > SPI_DELAY_RETRY)
+ return -EIO;
+ }
+
+ if (loop)
+ dev_dbg(controller->dev, "invalid state for %ld,us %d\n",
+ loop, 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);
+ }
+
+ loop = 0;
+ 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_fifo_read(struct spi_qup *controller,
+ struct spi_transfer *xfer)
+{
+ u8 *rx_buf = xfer->rx_buf;
+ u32 word, state;
+ int idx, shift, w_size;
+
+ w_size = controller->w_size;
+
+ 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);
+
+ if (!rx_buf) {
+ controller->rx_bytes += w_size;
+ continue;
+ }
+
+ for (idx = 0; idx < w_size; idx++, controller->rx_bytes++) {
+ /*
+ * The data format depends on bytes per SPI word:
+ * 4 bytes: 0x12345678
+ * 2 bytes: 0x00001234
+ * 1 byte : 0x00000012
+ */
+ shift = BITS_PER_BYTE;
+ shift *= (w_size - 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, w_size;
+
+ w_size = controller->w_size;
+
+ 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 < w_size; idx++, controller->tx_bytes++) {
+
+ if (!tx_buf) {
+ controller->tx_bytes += w_size;
+ break;
+ }
+
+ 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;
+ unsigned long flags;
+ int error = 0;
+
+ spin_lock_irqsave(&controller->lock, flags);
+ xfer = controller->xfer;
+ controller->xfer = NULL;
+ spin_unlock_irqrestore(&controller->lock, flags);
+
+ 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) {
+ dev_err_ratelimited(controller->dev, "unexpected irq %x08 %x08 %x08\n",
+ qup_err, spi_err, opflags);
+ 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");
+
+ 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");
+
+ error = -EIO;
+ }
+
+ if (opflags & QUP_OP_IN_SERVICE_FLAG)
+ spi_qup_fifo_read(controller, xfer);
+
+ if (opflags & QUP_OP_OUT_SERVICE_FLAG)
+ spi_qup_fifo_write(controller, xfer);
+
+ spin_lock_irqsave(&controller->lock, flags);
+ controller->error = error;
+ controller->xfer = xfer;
+ spin_unlock_irqrestore(&controller->lock, flags);
+
+ if (controller->rx_bytes == xfer->len || error)
+ complete(&controller->done);
+
+ return IRQ_HANDLED;
+}
+
+
+/* set clock freq ... bits per word */
+static int spi_qup_io_config(struct spi_qup *controller,
+ struct spi_qup_device *chip,
+ struct spi_transfer *xfer)
+{
+ u32 config, iomode, mode;
+ int ret, n_words, w_size;
+
+ if (chip->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;
+ }
+
+ ret = clk_set_rate(controller->cclk, xfer->speed_hz);
+ if (ret) {
+ dev_err(controller->dev, "fail to set frequency %d",
+ xfer->speed_hz);
+ return -EIO;
+ }
+
+ if (spi_qup_set_state(controller, QUP_STATE_RESET)) {
+ dev_err(controller->dev, "cannot set RESET state\n");
+ return -EIO;
+ }
+
+ w_size = 4;
+ if (xfer->bits_per_word <= 8)
+ w_size = 1;
+ else if (xfer->bits_per_word <= 16)
+ w_size = 2;
+
+ n_words = xfer->len / w_size;
+ controller->w_size = w_size;
+
+ 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 ((xfer->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 |= xfer->bits_per_word - 1;
+ config |= QUP_CONFIG_SPI_MODE;
+ writel_relaxed(config, controller->base + QUP_CONFIG);
+
+ writel_relaxed(0, controller->base + QUP_OPERATIONAL_MASK);
+ return 0;
+}
+
+static void spi_qup_set_cs(struct spi_device *spi, bool enable)
+{
+ struct spi_qup *controller = spi_master_get_devdata(spi->master);
+ struct spi_qup_device *chip = spi_get_ctldata(spi);
+
+ 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->select);
+
+ mask = SPI_IO_C_CS_N_POLARITY_0 << chip->select;
+
+ if (enable)
+ iocontol |= mask;
+ else
+ iocontol &= ~mask;
+
+ writel_relaxed(iocontol, controller->base + SPI_IO_CONTROL);
+}
+
+static int spi_qup_transfer_one(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ struct spi_qup *controller = spi_master_get_devdata(master);
+ struct spi_qup_device *chip = spi_get_ctldata(spi);
+ unsigned long timeout, flags;
+ int ret = -EIO;
+
+ ret = spi_qup_io_config(controller, chip, xfer);
+ if (ret)
+ return ret;
+
+ timeout = DIV_ROUND_UP(xfer->speed_hz, MSEC_PER_SEC);
+ timeout = DIV_ROUND_UP(xfer->len * 8, timeout);
+ timeout = 100 * msecs_to_jiffies(timeout);
+
+ reinit_completion(&controller->done);
+
+ spin_lock_irqsave(&controller->lock, flags);
+ controller->xfer = xfer;
+ controller->error = 0;
+ controller->rx_bytes = 0;
+ controller->tx_bytes = 0;
+ spin_unlock_irqrestore(&controller->lock, flags);
+
+ 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;
+exit:
+ spi_qup_set_state(controller, QUP_STATE_RESET);
+ spin_lock_irqsave(&controller->lock, flags);
+ controller->xfer = NULL;
+ if (!ret)
+ ret = controller->error;
+ spin_unlock_irqrestore(&controller->lock, flags);
+ 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;
+ }
+
+ chip->mode = spi->mode;
+ chip->select = spi->chip_select;
+ 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);
+}
+
+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))
+ return PTR_ERR(cclk);
+
+ iclk = devm_clk_get(dev, "iface");
+ if (IS_ERR(iclk))
+ return PTR_ERR(iclk);
+
+ /* This is optional parameter */
+ if (of_property_read_u32(dev->of_node, "spi-max-frequency", &max_freq))
+ max_freq = SPI_MAX_RATE;
+
+ if (!max_freq || max_freq > SPI_MAX_RATE) {
+ dev_err(dev, "invalid clock frequency %d\n", max_freq);
+ return -ENXIO;
+ }
+
+ 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->set_cs = spi_qup_set_cs;
+ master->transfer_one = spi_qup_transfer_one;
+ master->dev.of_node = pdev->dev.of_node;
+ master->auto_runtime_pm = true;
+
+ 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 = max_freq;
+
+ spin_lock_init(&controller->lock);
+ 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)
+ goto error;
+
+ ret = devm_spi_register_master(dev, master);
+ if (ret)
+ goto error;
+
+ pm_runtime_set_autosuspend_delay(dev, MSEC_PER_SEC);
+ pm_runtime_use_autosuspend(dev);
+ pm_runtime_set_active(dev);
+ pm_runtime_enable(dev);
+ return 0;
+
+error:
+ clk_disable_unprepare(cclk);
+ clk_disable_unprepare(iclk);
+ spi_master_put(master);
+ return ret;
+}
+
+#ifdef CONFIG_PM_RUNTIME
+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);
+ u32 config;
+
+ /* Enable clocks auto gaiting */
+ config = readl(controller->base + QUP_CONFIG);
+ config |= QUP_CLOCK_AUTO_GATE;
+ writel_relaxed(config, controller->base + QUP_CONFIG);
+ 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);
+ u32 config;
+
+ /* Disable clocks auto gaiting */
+ config = readl_relaxed(controller->base + QUP_CONFIG);
+ config &= ~QUP_CLOCK_AUTO_GATE;
+ writel_relaxed(config, controller->base + QUP_CONFIG);
+ 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 ret;
+
+ ret = spi_master_suspend(master);
+ if (ret)
+ return ret;
+
+ ret = spi_qup_set_state(controller, QUP_STATE_RESET);
+ if (ret)
+ return ret;
+
+ clk_disable_unprepare(controller->cclk);
+ clk_disable_unprepare(controller->iclk);
+ return 0;
+}
+
+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 ret;
+
+ ret = clk_prepare_enable(controller->iclk);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(controller->cclk);
+ if (ret)
+ return ret;
+
+ ret = spi_qup_set_state(controller, QUP_STATE_RESET);
+ if (ret)
+ return ret;
+
+ return spi_master_resume(master);
+}
+#endif /* CONFIG_PM_SLEEP */
+
+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);
+ int ret;
+
+ ret = pm_runtime_get_sync(&pdev->dev);
+ if (ret)
+ return ret;
+
+ ret = spi_qup_set_state(controller, QUP_STATE_RESET);
+ if (ret)
+ return ret;
+
+ clk_disable_unprepare(controller->cclk);
+ clk_disable_unprepare(controller->iclk);
+
+ pm_runtime_put_noidle(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+ spi_master_put(master);
+ return 0;
+}
+
+static struct of_device_id spi_qup_dt_match[] = {
+ { .compatible = "qcom,spi-qup-v2.1.1", },
+ { .compatible = "qcom,spi-qup-v2.2.1", },
+ { }
+};
+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)
+};
+
+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


2014-02-19 15:29:25

by Mark Brown

[permalink] [raw]
Subject: Re: [PATH v2 2/2] spi: Add Qualcomm QUP SPI controller support

On Thu, Feb 13, 2014 at 06:21:38PM +0200, Ivan T. Ivanov wrote:

> 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 supports up to 50MHz, up to four chip selects, programmable
> data path from 4 bits to 32 bits and numerous protocol variants.

I've applied this since it mostly looks good but there's a few small
outstanding issues, please submit incremental patches fixing them.

> +#define SPI_CONFIG 0x0300
> +#define SPI_IO_CONTROL 0x0304
> +#define SPI_ERROR_FLAGS 0x0308
> +#define SPI_ERROR_FLAGS_EN 0x030c

You've got lots of defines that are just plain SPI_ which is looking for
namespace collisions - please prefix them.

> + if (spi->chip_select >= spi->master->num_chipselect) {
> + dev_err(controller->dev, "invalid chip_select %d\n",
> + spi->chip_select);
> + return -EINVAL;
> + }

The core does this prior to allowing the slave to be registered at all.

> +
> + 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;
> + }

The core will check this for you if you set master->max_speed_hz.

> +#ifdef CONFIG_PM_RUNTIME
> +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);
> + u32 config;
> +
> + /* Enable clocks auto gaiting */
> + config = readl(controller->base + QUP_CONFIG);
> + config |= QUP_CLOCK_AUTO_GATE;
> + writel_relaxed(config, controller->base + QUP_CONFIG);
> + return 0;
> +}

Why not just enable this all the time? I'd have expected some clock API
calls here similar to those in the main suspend and resume paths.

> +MODULE_VERSION("0.4");

Don't bother doing this, nobody will ever keep updating the version
number - the kernel version should be enough.


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