[PATCH v2 13/14] spi: bcmbca-hsspi: Add driver for newer HSSPI controller
Jonas Gorski
jonas.gorski at gmail.com
Thu Jan 26 07:16:32 PST 2023
On Tue, 24 Jan 2023 at 23:33, William Zhang <william.zhang at broadcom.com> wrote:
>
> The newer BCMBCA SoCs such as BCM6756, BCM4912 and BCM6855 include an
> updated SPI controller that add the capability to allow the driver to
> control chip select explicitly. Driver can control and keep cs low
> between the transfers natively. Hence the dummy cs workaround or prepend
> mode found in the bcm63xx-hsspi driver are no longer needed and this new
> driver is much cleaner.
>
> Signed-off-by: William Zhang <william.zhang at broadcom.com>
>
> ---
>
> Changes in v2:
> - Fix build error for Alpha platform
> Reported-by: kernel test robot <lkp at intel.com>
> - Make interrupt as required node in the dts
> - Use polling mode as default mode
> - Add driver sysfs option wait_mode to allow mode change at run time
> - Update the compatible string based on changes in dts document
> - Remove clock gate disabling code for now
> - Update commit message
>
> drivers/spi/Kconfig | 9 +
> drivers/spi/Makefile | 1 +
> drivers/spi/spi-bcmbca-hsspi.c | 645 +++++++++++++++++++++++++++++++++
> 3 files changed, 655 insertions(+)
> create mode 100644 drivers/spi/spi-bcmbca-hsspi.c
>
> diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
> index 3b1c0878bb85..771244582d03 100644
> --- a/drivers/spi/Kconfig
> +++ b/drivers/spi/Kconfig
> @@ -199,6 +199,15 @@ config SPI_BCM_QSPI
> based platforms. This driver works for both SPI master for SPI NOR
> flash device as well as MSPI device.
>
> +config SPI_BCMBCA_HSSPI
> + tristate "Broadcom BCMBCA HS SPI controller driver"
> + depends on ARCH_BCMBCA || COMPILE_TEST
> + help
> + This enables support for the High Speed SPI controller present on
> + newer Broadcom BCMBCA SoCs. These SoCs include an updated SPI controller
> + that adds the capability to allow the driver to control chip select
> + explicitly.
> +
> config SPI_BITBANG
> tristate "Utilities for Bitbanging SPI masters"
> help
> diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
> index be9ba40ef8d0..fe92106447c3 100644
> --- a/drivers/spi/Makefile
> +++ b/drivers/spi/Makefile
> @@ -30,6 +30,7 @@ obj-$(CONFIG_SPI_BCM2835) += spi-bcm2835.o
> obj-$(CONFIG_SPI_BCM2835AUX) += spi-bcm2835aux.o
> obj-$(CONFIG_SPI_BCM63XX) += spi-bcm63xx.o
> obj-$(CONFIG_SPI_BCM63XX_HSSPI) += spi-bcm63xx-hsspi.o
> +obj-$(CONFIG_SPI_BCMBCA_HSSPI) += spi-bcmbca-hsspi.o
> obj-$(CONFIG_SPI_BCM_QSPI) += spi-iproc-qspi.o spi-brcmstb-qspi.o spi-bcm-qspi.o
> obj-$(CONFIG_SPI_BITBANG) += spi-bitbang.o
> obj-$(CONFIG_SPI_BUTTERFLY) += spi-butterfly.o
> diff --git a/drivers/spi/spi-bcmbca-hsspi.c b/drivers/spi/spi-bcmbca-hsspi.c
> new file mode 100644
> index 000000000000..f8da194939c0
> --- /dev/null
> +++ b/drivers/spi/spi-bcmbca-hsspi.c
> @@ -0,0 +1,645 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Broadcom BCMBCA High Speed SPI Controller driver
> + *
> + * Copyright 2000-2010 Broadcom Corporation
> + * Copyright 2012-2013 Jonas Gorski <jogo at openwrt.org>
> + * Copyright 2019-2022 Broadcom Ltd
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/init.h>
> +#include <linux/io.h>
> +#include <linux/clk.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/delay.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/err.h>
> +#include <linux/interrupt.h>
> +#include <linux/spi/spi.h>
> +#include <linux/mutex.h>
> +#include <linux/of.h>
> +#include <linux/spi/spi-mem.h>
> +#include <linux/pm_runtime.h>
> +
> +#define HSSPI_GLOBAL_CTRL_REG 0x0
> +#define GLOBAL_CTRL_CS_POLARITY_SHIFT 0
> +#define GLOBAL_CTRL_CS_POLARITY_MASK 0x000000ff
> +#define GLOBAL_CTRL_PLL_CLK_CTRL_SHIFT 8
> +#define GLOBAL_CTRL_PLL_CLK_CTRL_MASK 0x0000ff00
> +#define GLOBAL_CTRL_CLK_GATE_SSOFF BIT(16)
> +#define GLOBAL_CTRL_CLK_POLARITY BIT(17)
> +#define GLOBAL_CTRL_MOSI_IDLE BIT(18)
> +
> +#define HSSPI_GLOBAL_EXT_TRIGGER_REG 0x4
> +
> +#define HSSPI_INT_STATUS_REG 0x8
> +#define HSSPI_INT_STATUS_MASKED_REG 0xc
> +#define HSSPI_INT_MASK_REG 0x10
> +
> +#define HSSPI_PINGx_CMD_DONE(i) BIT((i * 8) + 0)
> +#define HSSPI_PINGx_RX_OVER(i) BIT((i * 8) + 1)
> +#define HSSPI_PINGx_TX_UNDER(i) BIT((i * 8) + 2)
> +#define HSSPI_PINGx_POLL_TIMEOUT(i) BIT((i * 8) + 3)
> +#define HSSPI_PINGx_CTRL_INVAL(i) BIT((i * 8) + 4)
> +
> +#define HSSPI_INT_CLEAR_ALL 0xff001f1f
> +
> +#define HSSPI_PINGPONG_COMMAND_REG(x) (0x80 + (x) * 0x40)
> +#define PINGPONG_CMD_COMMAND_MASK 0xf
> +#define PINGPONG_COMMAND_NOOP 0
> +#define PINGPONG_COMMAND_START_NOW 1
> +#define PINGPONG_COMMAND_START_TRIGGER 2
> +#define PINGPONG_COMMAND_HALT 3
> +#define PINGPONG_COMMAND_FLUSH 4
> +#define PINGPONG_CMD_PROFILE_SHIFT 8
> +#define PINGPONG_CMD_SS_SHIFT 12
> +
> +#define HSSPI_PINGPONG_STATUS_REG(x) (0x84 + (x) * 0x40)
> +#define HSSPI_PINGPONG_STATUS_SRC_BUSY BIT(1)
> +
> +#define HSSPI_PROFILE_CLK_CTRL_REG(x) (0x100 + (x) * 0x20)
> +#define CLK_CTRL_FREQ_CTRL_MASK 0x0000ffff
> +#define CLK_CTRL_SPI_CLK_2X_SEL BIT(14)
> +#define CLK_CTRL_ACCUM_RST_ON_LOOP BIT(15)
> +#define CLK_CTRL_CLK_POLARITY BIT(16)
> +
> +#define HSSPI_PROFILE_SIGNAL_CTRL_REG(x) (0x104 + (x) * 0x20)
> +#define SIGNAL_CTRL_LATCH_RISING BIT(12)
> +#define SIGNAL_CTRL_LAUNCH_RISING BIT(13)
> +#define SIGNAL_CTRL_ASYNC_INPUT_PATH BIT(16)
> +
> +#define HSSPI_PROFILE_MODE_CTRL_REG(x) (0x108 + (x) * 0x20)
> +#define MODE_CTRL_MULTIDATA_RD_STRT_SHIFT 8
> +#define MODE_CTRL_MULTIDATA_WR_STRT_SHIFT 12
> +#define MODE_CTRL_MULTIDATA_RD_SIZE_SHIFT 16
> +#define MODE_CTRL_MULTIDATA_WR_SIZE_SHIFT 18
> +#define MODE_CTRL_MODE_3WIRE BIT(20)
> +#define MODE_CTRL_PREPENDBYTE_CNT_SHIFT 24
> +
> +#define HSSPI_FIFO_REG(x) (0x200 + (x) * 0x200)
> +
> +#define HSSPI_OP_MULTIBIT BIT(11)
> +#define HSSPI_OP_CODE_SHIFT 13
> +#define HSSPI_OP_SLEEP (0 << HSSPI_OP_CODE_SHIFT)
> +#define HSSPI_OP_READ_WRITE (1 << HSSPI_OP_CODE_SHIFT)
> +#define HSSPI_OP_WRITE (2 << HSSPI_OP_CODE_SHIFT)
> +#define HSSPI_OP_READ (3 << HSSPI_OP_CODE_SHIFT)
> +#define HSSPI_OP_SETIRQ (4 << HSSPI_OP_CODE_SHIFT)
> +
> +#define HSSPI_BUFFER_LEN 512
> +#define HSSPI_OPCODE_LEN 2
> +
> +#define HSSPI_MAX_PREPEND_LEN 15
> +
> +#define HSSPI_MAX_SYNC_CLOCK 30000000
> +
> +#define HSSPI_SPI_MAX_CS 8
> +#define HSSPI_BUS_NUM 1 /* 0 is legacy SPI */
> +#define HSSPI_POLL_STATUS_TIMEOUT_MS 100
> +
> +#define HSSPI_WAIT_MODE_POLLING 0
> +#define HSSPI_WAIT_MODE_INTR 1
> +#define HSSPI_WAIT_MODE_MAX HSSPI_WAIT_MODE_INTR
> +
> +#define SPIM_CTRL_CS_OVERRIDE_SEL_SHIFT 0
> +#define SPIM_CTRL_CS_OVERRIDE_SEL_MASK 0xff
> +#define SPIM_CTRL_CS_OVERRIDE_VAL_SHIFT 8
> +#define SPIM_CTRL_CS_OVERRIDE_VAL_MASK 0xff
> +
> +struct bcmbca_hsspi {
> + struct completion done;
> + struct mutex bus_mutex;
> + struct mutex msg_mutex;
> + struct platform_device *pdev;
> + struct clk *clk;
> + struct clk *pll_clk;
> + void __iomem *regs;
> + void __iomem *spim_ctrl;
> + u8 __iomem *fifo;
> + u32 speed_hz;
> + u8 cs_polarity;
> + u32 wait_mode;
> +};
> +
> +static ssize_t wait_mode_show(struct device *dev, struct device_attribute *attr,
> + char *buf)
> +{
> + struct spi_controller *ctrl = dev_get_drvdata(dev);
> + struct bcmbca_hsspi *bs = spi_master_get_devdata(ctrl);
> +
> + return sprintf(buf, "%d\n", bs->wait_mode);
> +}
> +
> +static ssize_t wait_mode_store(struct device *dev, struct device_attribute *attr,
> + const char *buf, size_t count)
> +{
> + struct spi_controller *ctrl = dev_get_drvdata(dev);
> + struct bcmbca_hsspi *bs = spi_master_get_devdata(ctrl);
> + u32 val;
> +
> + if (kstrtou32(buf, 10, &val))
> + return -EINVAL;
> +
> + if (val > HSSPI_WAIT_MODE_MAX) {
> + dev_warn(dev, "invalid wait mode %u\n", val);
> + return -EINVAL;
> + }
> +
> + mutex_lock(&bs->msg_mutex);
> + bs->wait_mode = val;
> + /* clear interrupt status to avoid spurious int on next transfer */
> + if (val == HSSPI_WAIT_MODE_INTR)
> + __raw_writel(HSSPI_INT_CLEAR_ALL, bs->regs + HSSPI_INT_STATUS_REG);
> + mutex_unlock(&bs->msg_mutex);
> +
> + return count;
> +}
> +
> +static DEVICE_ATTR_RW(wait_mode);
> +
> +static struct attribute *bcmbca_hsspi_attrs[] = {
> + &dev_attr_wait_mode.attr,
> + NULL,
> +};
> +
> +static const struct attribute_group bcmbca_hsspi_group = {
> + .attrs = bcmbca_hsspi_attrs,
> +};
> +
> +static void bcmbca_hsspi_set_clk(struct bcmbca_hsspi *bs,
> + struct spi_device *spi, int hz);
> +
> +static void bcmbca_hsspi_set_cs(struct bcmbca_hsspi *bs, unsigned int cs,
> + bool active)
> +{
> + u32 reg;
> +
> + /* No cs orerriden needed for SS7 internal cs on pcm based voice dev */
> + if (cs == 7)
> + return;
> +
> + mutex_lock(&bs->bus_mutex);
> +
> + if (active) {
> + /* activate cs by setting the override bit and active value bit*/
> + reg = __raw_readl(bs->spim_ctrl);
> + reg |= BIT(cs+SPIM_CTRL_CS_OVERRIDE_SEL_SHIFT);
Doesn't checkpatch complain about missing spaces around the operator (+)?
> + reg &= ~BIT(cs+SPIM_CTRL_CS_OVERRIDE_VAL_SHIFT);
> + if (bs->cs_polarity & BIT(cs))
> + reg |= BIT(cs+SPIM_CTRL_CS_OVERRIDE_VAL_SHIFT);
Does the CS_OVERRIDE_VAL get reset on clearing the OVERRIDE_SEL bit or
it is persistent? If the latter, you could initialize its value in
bcmbca_hsspi_setup() and then this becomes:
reg = _raw_readl(bs->spim_ctrl);
if (active)
reg |= BIT(cs+SPIM_CTRL_CS_OVERRIDE_SEL_SHIFT);
else
reg &= ~BIT(cs + SPIM_CTRL_CS_OVERRIDE_SEL_SHIFT);
__raw_writel(reg, bs->spim_ctrl);
and you can drop the cs_polarity field.
> + __raw_writel(reg, bs->spim_ctrl);
> + } else {
> + /* clear the cs override bit */
> + reg = __raw_readl(bs->spim_ctrl);
> + reg &= ~BIT(cs+SPIM_CTRL_CS_OVERRIDE_SEL_SHIFT);
> + __raw_writel(reg, bs->spim_ctrl);
> + }
> +
> + mutex_unlock(&bs->bus_mutex);
> +}
> +
> +static void bcmbca_hsspi_set_clk(struct bcmbca_hsspi *bs,
> + struct spi_device *spi, int hz)
> +{
> + unsigned int profile = spi->chip_select;
> + u32 reg;
> +
> + reg = DIV_ROUND_UP(2048, DIV_ROUND_UP(bs->speed_hz, hz));
> + __raw_writel(CLK_CTRL_ACCUM_RST_ON_LOOP | reg,
> + bs->regs + HSSPI_PROFILE_CLK_CTRL_REG(profile));
> +
> + reg = __raw_readl(bs->regs + HSSPI_PROFILE_SIGNAL_CTRL_REG(profile));
> + if (hz > HSSPI_MAX_SYNC_CLOCK)
> + reg |= SIGNAL_CTRL_ASYNC_INPUT_PATH;
> + else
> + reg &= ~SIGNAL_CTRL_ASYNC_INPUT_PATH;
> + __raw_writel(reg, bs->regs + HSSPI_PROFILE_SIGNAL_CTRL_REG(profile));
> +
> + mutex_lock(&bs->bus_mutex);
> + /* setup clock polarity */
> + reg = __raw_readl(bs->regs + HSSPI_GLOBAL_CTRL_REG);
> + reg &= ~GLOBAL_CTRL_CLK_POLARITY;
> + if (spi->mode & SPI_CPOL)
> + reg |= GLOBAL_CTRL_CLK_POLARITY;
> +
> + __raw_writel(reg, bs->regs + HSSPI_GLOBAL_CTRL_REG);
> +
> + mutex_unlock(&bs->bus_mutex);
> +}
> +
> +static int bcmbca_hsspi_wait_cmd(struct bcmbca_hsspi *bs, unsigned int cs)
> +{
> + unsigned long limit;
> + u32 reg = 0;
> + int rc = 0;
> +
> + if (bs->wait_mode == HSSPI_WAIT_MODE_INTR) {
> + if (wait_for_completion_timeout(&bs->done, HZ) == 0)
> + rc = 1;
> + } else {
> + limit = jiffies + msecs_to_jiffies(HSSPI_POLL_STATUS_TIMEOUT_MS);
> +
> + while (!time_after(jiffies, limit)) {
> + reg = __raw_readl(bs->regs + HSSPI_PINGPONG_STATUS_REG(0));
> + if (reg & HSSPI_PINGPONG_STATUS_SRC_BUSY)
> + cpu_relax();
> + else
> + break;
> + }
> + if (reg & HSSPI_PINGPONG_STATUS_SRC_BUSY)
> + rc = 1;
> + }
> +
> + if (rc) {
> + dev_err(&bs->pdev->dev, "transfer timed out!\n");
> + bcmbca_hsspi_set_cs(bs, cs, false);
> + }
> +
> + return rc;
> +}
> +
> +static int bcmbca_hsspi_do_txrx(struct spi_device *spi, struct spi_transfer *t,
> + struct spi_message *msg)
> +{
> + struct bcmbca_hsspi *bs = spi_master_get_devdata(spi->master);
> + unsigned int chip_select = spi->chip_select;
> + u16 opcode = 0;
> + int pending = t->len;
> + int step_size = HSSPI_BUFFER_LEN;
> + const u8 *tx = t->tx_buf;
> + u8 *rx = t->rx_buf;
> + u32 reg = 0, cs_act = 0;
> +
> + bcmbca_hsspi_set_clk(bs, spi, t->speed_hz);
> +
> + if (tx && rx)
> + opcode = HSSPI_OP_READ_WRITE;
> + else if (tx)
> + opcode = HSSPI_OP_WRITE;
> + else if (rx)
> + opcode = HSSPI_OP_READ;
> +
> + if (opcode != HSSPI_OP_READ)
> + step_size -= HSSPI_OPCODE_LEN;
> +
> + if ((opcode == HSSPI_OP_READ && t->rx_nbits == SPI_NBITS_DUAL) ||
> + (opcode == HSSPI_OP_WRITE && t->tx_nbits == SPI_NBITS_DUAL)) {
> + opcode |= HSSPI_OP_MULTIBIT;
> +
> + if (t->rx_nbits == SPI_NBITS_DUAL)
> + reg |= 1 << MODE_CTRL_MULTIDATA_RD_SIZE_SHIFT;
> + if (t->tx_nbits == SPI_NBITS_DUAL)
> + reg |= 1 << MODE_CTRL_MULTIDATA_WR_SIZE_SHIFT;
> + }
> +
> + __raw_writel(reg | 0xff,
> + bs->regs + HSSPI_PROFILE_MODE_CTRL_REG(chip_select));
> +
> + while (pending > 0) {
> + int curr_step = min_t(int, step_size, pending);
> +
> + reinit_completion(&bs->done);
> + if (tx) {
> + memcpy_toio(bs->fifo + HSSPI_OPCODE_LEN, tx, curr_step);
> + tx += curr_step;
> + }
> + __raw_writew((u16)cpu_to_be16(opcode | curr_step), bs->fifo);
> +
> + /* enable interrupt */
> + if (bs->wait_mode == HSSPI_WAIT_MODE_INTR)
> + __raw_writel(HSSPI_PINGx_CMD_DONE(0),
> + bs->regs + HSSPI_INT_MASK_REG);
> +
> + if (!cs_act) {
> + bcmbca_hsspi_set_cs(bs, chip_select, true);
> + cs_act = 1;
> + }
> + reg = chip_select << PINGPONG_CMD_SS_SHIFT |
> + chip_select << PINGPONG_CMD_PROFILE_SHIFT |
> + PINGPONG_COMMAND_START_NOW;
> + __raw_writel(reg, bs->regs + HSSPI_PINGPONG_COMMAND_REG(0));
> +
> + if (bcmbca_hsspi_wait_cmd(bs, spi->chip_select))
> + return -ETIMEDOUT;
> +
> + pending -= curr_step;
> + if (pending == 0) {
> + if (list_is_last(&t->transfer_list, &msg->transfers)) {
> + if (!t->cs_change)
> + bcmbca_hsspi_set_cs(bs, spi->chip_select, false);
> + } else {
> + if (t->cs_change) {
> + bcmbca_hsspi_set_cs(bs, spi->chip_select, false);
> + udelay(10);
> + bcmbca_hsspi_set_cs(bs, spi->chip_select, true);
> + }
> + }
> + }
> + if (rx) {
> + memcpy_fromio(rx, bs->fifo, curr_step);
> + rx += curr_step;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static int bcmbca_hsspi_setup(struct spi_device *spi)
> +{
> + struct bcmbca_hsspi *bs = spi_master_get_devdata(spi->master);
> + u32 reg;
> +
> + reg = __raw_readl(bs->regs +
> + HSSPI_PROFILE_SIGNAL_CTRL_REG(spi->chip_select));
> + reg &= ~(SIGNAL_CTRL_LAUNCH_RISING | SIGNAL_CTRL_LATCH_RISING);
> + if (spi->mode & SPI_CPHA)
> + reg |= SIGNAL_CTRL_LAUNCH_RISING;
> + else
> + reg |= SIGNAL_CTRL_LATCH_RISING;
> + __raw_writel(reg, bs->regs +
> + HSSPI_PROFILE_SIGNAL_CTRL_REG(spi->chip_select));
> +
> + mutex_lock(&bs->bus_mutex);
> + reg = __raw_readl(bs->regs + HSSPI_GLOBAL_CTRL_REG);
> +
> + if (spi->mode & SPI_CS_HIGH)
> + reg |= BIT(spi->chip_select);
> + else
> + reg &= ~BIT(spi->chip_select);
> + __raw_writel(reg, bs->regs + HSSPI_GLOBAL_CTRL_REG);
> +
> + if (spi->mode & SPI_CS_HIGH)
> + bs->cs_polarity |= BIT(spi->chip_select);
> + else
> + bs->cs_polarity &= ~BIT(spi->chip_select);
> +
> + mutex_unlock(&bs->bus_mutex);
> +
> + return 0;
> +}
> +
> +static int bcmbca_hsspi_transfer_one(struct spi_master *master,
> + struct spi_message *msg)
> +{
> + struct bcmbca_hsspi *bs = spi_master_get_devdata(master);
> + struct spi_transfer *t;
> + struct spi_device *spi = msg->spi;
> + int status = -EINVAL;
> +
> + mutex_lock(&bs->msg_mutex);
> + list_for_each_entry(t, &msg->transfers, transfer_list) {
> + status = bcmbca_hsspi_do_txrx(spi, t, msg);
> + if (status)
> + break;
> +
> + msg->actual_length += t->len;
> +
> + spi_transfer_delay_exec(t);
> + }
> +
> + mutex_unlock(&bs->msg_mutex);
> + msg->status = status;
> + spi_finalize_current_message(master);
> +
> + return 0;
> +}
> +
> +static irqreturn_t bcmbca_hsspi_interrupt(int irq, void *dev_id)
> +{
> + struct bcmbca_hsspi *bs = (struct bcmbca_hsspi *)dev_id;
> +
> + if (__raw_readl(bs->regs + HSSPI_INT_STATUS_MASKED_REG) == 0)
> + return IRQ_NONE;
> +
> + __raw_writel(HSSPI_INT_CLEAR_ALL, bs->regs + HSSPI_INT_STATUS_REG);
> + __raw_writel(0, bs->regs + HSSPI_INT_MASK_REG);
> +
> + complete(&bs->done);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int bcmbca_hsspi_probe(struct platform_device *pdev)
> +{
> + struct spi_master *master;
> + struct bcmbca_hsspi *bs;
> + struct resource *res_mem;
> + void __iomem *spim_ctrl;
> + void __iomem *regs;
> + struct device *dev = &pdev->dev;
> + struct clk *clk, *pll_clk = NULL;
> + int irq, ret;
> + u32 reg, rate, num_cs = HSSPI_SPI_MAX_CS;
> +
> + irq = platform_get_irq(pdev, 0);
> + if (irq < 0)
> + return irq;
> +
> + res_mem = platform_get_resource_byname(pdev, IORESOURCE_MEM, "hsspi");
> + if (!res_mem)
> + return -EINVAL;
> + regs = devm_ioremap_resource(dev, res_mem);
> + if (IS_ERR(regs))
> + return PTR_ERR(regs);
> +
> + res_mem = platform_get_resource_byname(pdev, IORESOURCE_MEM, "spim-ctrl");
> + if (!res_mem)
> + return -EINVAL;
> + spim_ctrl = devm_ioremap_resource(dev, res_mem);
> + if (IS_ERR(spim_ctrl))
> + return PTR_ERR(spim_ctrl);
> +
> + clk = devm_clk_get(dev, "hsspi");
> + if (IS_ERR(clk))
> + return PTR_ERR(clk);
> +
> + ret = clk_prepare_enable(clk);
> + if (ret)
> + return ret;
> +
> + rate = clk_get_rate(clk);
> + if (!rate) {
> + pll_clk = devm_clk_get(dev, "pll");
> +
> + if (IS_ERR(pll_clk)) {
> + ret = PTR_ERR(pll_clk);
> + goto out_disable_clk;
> + }
> +
> + ret = clk_prepare_enable(pll_clk);
> + if (ret)
> + goto out_disable_clk;
> +
> + rate = clk_get_rate(pll_clk);
> + if (!rate) {
> + ret = -EINVAL;
> + goto out_disable_pll_clk;
> + }
> + }
> +
> + master = spi_alloc_master(&pdev->dev, sizeof(*bs));
> + if (!master) {
> + ret = -ENOMEM;
> + goto out_disable_pll_clk;
> + }
> +
> + bs = spi_master_get_devdata(master);
> + bs->pdev = pdev;
> + bs->clk = clk;
> + bs->pll_clk = pll_clk;
> + bs->regs = regs;
> + bs->spim_ctrl = spim_ctrl;
> + bs->speed_hz = rate;
> + bs->fifo = (u8 __iomem *) (bs->regs + HSSPI_FIFO_REG(0));
> + bs->wait_mode = HSSPI_WAIT_MODE_POLLING;
> +
> + mutex_init(&bs->bus_mutex);
> + mutex_init(&bs->msg_mutex);
> + init_completion(&bs->done);
> +
> + master->dev.of_node = dev->of_node;
> + if (!dev->of_node)
> + master->bus_num = HSSPI_BUS_NUM;
> +
> + of_property_read_u32(dev->of_node, "num-cs", &num_cs);
> + if (num_cs > 8) {
> + dev_warn(dev, "unsupported number of cs (%i), reducing to 8\n",
> + num_cs);
> + num_cs = HSSPI_SPI_MAX_CS;
> + }
> + master->num_chipselect = num_cs;
> + master->setup = bcmbca_hsspi_setup;
> + master->transfer_one_message = bcmbca_hsspi_transfer_one;
> + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH |
> + SPI_RX_DUAL | SPI_TX_DUAL;
> + master->bits_per_word_mask = SPI_BPW_MASK(8);
> + master->auto_runtime_pm = true;
> +
> + platform_set_drvdata(pdev, master);
> +
> + /* Initialize the hardware */
> + __raw_writel(0, bs->regs + HSSPI_INT_MASK_REG);
> +
> + /* clean up any pending interrupts */
> + __raw_writel(HSSPI_INT_CLEAR_ALL, bs->regs + HSSPI_INT_STATUS_REG);
> +
> + /* read out default CS polarities */
> + reg = __raw_readl(bs->regs + HSSPI_GLOBAL_CTRL_REG);
> + bs->cs_polarity = reg & GLOBAL_CTRL_CS_POLARITY_MASK;
> + __raw_writel(reg | GLOBAL_CTRL_CLK_GATE_SSOFF,
> + bs->regs + HSSPI_GLOBAL_CTRL_REG);
> +
> + if (irq > 0) {
> + ret = devm_request_irq(dev, irq, bcmbca_hsspi_interrupt, IRQF_SHARED,
> + pdev->name, bs);
> + if (ret)
> + goto out_put_master;
> + }
> +
> + pm_runtime_enable(&pdev->dev);
> +
> + if (sysfs_create_group(&pdev->dev.kobj, &bcmbca_hsspi_group)) {
> + dev_err(&pdev->dev, "couldn't register sysfs group\n");
> + goto out_pm_disable;
> + }
> +
> + /* register and we are done */
> + ret = devm_spi_register_master(dev, master);
> + if (ret)
> + goto out_sysgroup_disable;
> +
> + dev_info(dev, "Broadcom BCMBCA High Speed SPI Controller driver");
> +
> + return 0;
> +
> +out_sysgroup_disable:
> + sysfs_remove_group(&pdev->dev.kobj, &bcmbca_hsspi_group);
> +out_pm_disable:
> + pm_runtime_disable(&pdev->dev);
> +out_put_master:
> + spi_master_put(master);
> +out_disable_pll_clk:
> + clk_disable_unprepare(pll_clk);
> +out_disable_clk:
> + clk_disable_unprepare(clk);
> + return ret;
> +}
> +
> +static int bcmbca_hsspi_remove(struct platform_device *pdev)
> +{
> + struct spi_master *master = platform_get_drvdata(pdev);
> + struct bcmbca_hsspi *bs = spi_master_get_devdata(master);
> +
> + /* reset the hardware and block queue progress */
> + __raw_writel(0, bs->regs + HSSPI_INT_MASK_REG);
> + clk_disable_unprepare(bs->pll_clk);
> + clk_disable_unprepare(bs->clk);
> + sysfs_remove_group(&pdev->dev.kobj, &bcmbca_hsspi_group);
> +
> + return 0;
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int bcmbca_hsspi_suspend(struct device *dev)
> +{
> + struct spi_master *master = dev_get_drvdata(dev);
> + struct bcmbca_hsspi *bs = spi_master_get_devdata(master);
> +
> + spi_master_suspend(master);
> + clk_disable_unprepare(bs->pll_clk);
> + clk_disable_unprepare(bs->clk);
> +
> + return 0;
> +}
> +
> +static int bcmbca_hsspi_resume(struct device *dev)
> +{
> + struct spi_master *master = dev_get_drvdata(dev);
> + struct bcmbca_hsspi *bs = spi_master_get_devdata(master);
> + int ret;
> +
> + ret = clk_prepare_enable(bs->clk);
> + if (ret)
> + return ret;
> +
> + if (bs->pll_clk) {
> + ret = clk_prepare_enable(bs->pll_clk);
> + if (ret) {
> + clk_disable_unprepare(bs->clk);
> + return ret;
> + }
> + }
> +
> + spi_master_resume(master);
> +
> + return 0;
> +}
> +#endif
> +
> +static SIMPLE_DEV_PM_OPS(bcmbca_hsspi_pm_ops, bcmbca_hsspi_suspend,
> + bcmbca_hsspi_resume);
> +
> +static const struct of_device_id bcmbca_hsspi_of_match[] = {
> + { .compatible = "brcm,bcmbca-hsspi-v1.1", },
> + {},
> +};
> +
> +MODULE_DEVICE_TABLE(of, bcmbca_hsspi_of_match);
> +
> +static struct platform_driver bcmbca_hsspi_driver = {
> + .driver = {
> + .name = "bcmbca-hsspi",
> + .pm = &bcmbca_hsspi_pm_ops,
> + .of_match_table = bcmbca_hsspi_of_match,
> + },
> + .probe = bcmbca_hsspi_probe,
> + .remove = bcmbca_hsspi_remove,
> +};
> +
> +module_platform_driver(bcmbca_hsspi_driver);
> +
> +MODULE_ALIAS("platform:bcmbca_hsspi");
> +MODULE_DESCRIPTION("Broadcom BCMBCA High Speed SPI Controller driver");
> +MODULE_LICENSE("GPL");
> --
> 2.37.3
>
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