This patch adds the binding documentation for Spreadtrum ADI
controller device.
Signed-off-by: Baolin Wang <[email protected]>
---
Changes since v2:
- Add some documentation to describe how many hardware channels can be
configured.
- Remove "SPI framework" from binding file and other small optimization.
Changes since v1:
- Add more documentation for the 'sprd,hw-channels' property and explain
why need one hardware spinlock.
---
.../devicetree/bindings/spi/spi-sprd-adi.txt | 58 ++++++++++++++++++++
1 file changed, 58 insertions(+)
create mode 100644 Documentation/devicetree/bindings/spi/spi-sprd-adi.txt
diff --git a/Documentation/devicetree/bindings/spi/spi-sprd-adi.txt b/Documentation/devicetree/bindings/spi/spi-sprd-adi.txt
new file mode 100644
index 0000000..8de589b
--- /dev/null
+++ b/Documentation/devicetree/bindings/spi/spi-sprd-adi.txt
@@ -0,0 +1,58 @@
+Spreadtrum ADI controller
+
+ADI is the abbreviation of Anolog-Digital interface, which is used to access
+analog chip (such as PMIC) from digital chip. ADI controller follows the SPI
+framework for its hardware implementation is alike to SPI bus and its timing
+is compatile to SPI timing.
+
+ADI controller has 50 channels including 2 software read/write channels and
+48 hardware channels to access analog chip. For 2 software read/write channels,
+users should set ADI registers to access analog chip. For hardware channels,
+we can configure them to allow other hardware components to use it independently,
+which means we can just link one analog chip address to one hardware channel,
+then users can access the mapped analog chip address by this hardware channel
+triggered by hardware components instead of ADI software channels.
+
+Thus we introduce one property named "sprd,hw-channels" to configure hardware
+channels, the first value specifies the hardware channel id which is used to
+transfer data triggered by hardware automatically, and the second value specifies
+the analog chip address where user want to access by hardware components.
+
+Since we have multi-subsystems will use unique ADI to access analog chip, when
+one system is reading/writing data by ADI software channels, that should be under
+one hardware spinlock protection to prevent other systems from reading/writing
+data by ADI software channels at the same time, or two parallel routine of setting
+ADI registers will make ADI controller registers chaos to lead incorrect results.
+Then we need one hardware spinlock to synchronize between the multiple subsystems.
+
+Required properties:
+- compatible: Should be "sprd,sc9860-adi".
+- reg: Offset and length of ADI-SPI controller register space.
+- hwlocks: Reference to a phandle of a hwlock provider node.
+- hwlock-names: Reference to hwlock name strings defined in the same order
+ as the hwlocks, should be "adi".
+- #address-cells: Number of cells required to define a chip select address
+ on the ADI-SPI bus. Should be set to 1.
+- #size-cells: Size of cells required to define a chip select address size
+ on the ADI-SPI bus. Should be set to 0.
+
+Optional properties:
+- sprd,hw-channels: This is an array of channel values up to 49 channels.
+ The first value specifies the hardware channel id which is used to
+ transfer data triggered by hardware automatically, and the second
+ value specifies the analog chip address where user want to access
+ by hardware components.
+
+SPI slave nodes must be children of the SPI controller node and can contain
+properties described in Documentation/devicetree/bindings/spi/spi-bus.txt.
+
+Example:
+ adi_bus: spi@40030000 {
+ compatible = "sprd,sc9860-adi";
+ reg = <0 0x40030000 0 0x10000>;
+ hwlocks = <&hwlock1 0>;
+ hwlock-names = "adi";
+ #address-cells = <1>;
+ #size-cells = <0>;
+ sprd,hw-channels = <30 0x8c20>;
+ };
--
1.7.9.5
This patch adds ADI driver based on SPI framework for
Spreadtrum SC9860 platform.
Signed-off-by: Baolin Wang <[email protected]>
---
Changes since v2:
- Remove the MIT license.
Changes since v1:
- Add COMPILE_TEST config as dependency.
- Remove spi_controller_put() function when removing driver.
- Change to module_init() level.
---
drivers/spi/Kconfig | 6 +
drivers/spi/Makefile | 1 +
drivers/spi/spi-sprd-adi.c | 419 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 426 insertions(+)
create mode 100644 drivers/spi/spi-sprd-adi.c
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 9b31351..fbdced7 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -627,6 +627,12 @@ config SPI_SIRF
help
SPI driver for CSR SiRFprimaII SoCs
+config SPI_SPRD_ADI
+ tristate "Spreadtrum ADI controller"
+ depends on ARCH_SPRD || COMPILE_TEST
+ help
+ ADI driver based on SPI for Spreadtrum SoCs.
+
config SPI_STM32
tristate "STMicroelectronics STM32 SPI controller"
depends on ARCH_STM32 || COMPILE_TEST
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index a3ae2b7..de5ae2a 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -90,6 +90,7 @@ obj-$(CONFIG_SPI_SH_HSPI) += spi-sh-hspi.o
obj-$(CONFIG_SPI_SH_MSIOF) += spi-sh-msiof.o
obj-$(CONFIG_SPI_SH_SCI) += spi-sh-sci.o
obj-$(CONFIG_SPI_SIRF) += spi-sirf.o
+obj-$(CONFIG_SPI_SPRD_ADI) += spi-sprd-adi.o
obj-$(CONFIG_SPI_STM32) += spi-stm32.o
obj-$(CONFIG_SPI_ST_SSC4) += spi-st-ssc4.o
obj-$(CONFIG_SPI_SUN4I) += spi-sun4i.o
diff --git a/drivers/spi/spi-sprd-adi.c b/drivers/spi/spi-sprd-adi.c
new file mode 100644
index 0000000..0d481f8
--- /dev/null
+++ b/drivers/spi/spi-sprd-adi.c
@@ -0,0 +1,419 @@
+/*
+ * Copyright (C) 2017 Spreadtrum Communications Inc.
+ *
+ * SPDX-License-Identifier: GPL-2.0
+ */
+
+#include <linux/hwspinlock.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.h>
+#include <linux/sizes.h>
+
+/* Registers definitions for ADI controller */
+#define REG_ADI_CTRL0 0x4
+#define REG_ADI_CHN_PRIL 0x8
+#define REG_ADI_CHN_PRIH 0xc
+#define REG_ADI_INT_EN 0x10
+#define REG_ADI_INT_RAW 0x14
+#define REG_ADI_INT_MASK 0x18
+#define REG_ADI_INT_CLR 0x1c
+#define REG_ADI_GSSI_CFG0 0x20
+#define REG_ADI_GSSI_CFG1 0x24
+#define REG_ADI_RD_CMD 0x28
+#define REG_ADI_RD_DATA 0x2c
+#define REG_ADI_ARM_FIFO_STS 0x30
+#define REG_ADI_STS 0x34
+#define REG_ADI_EVT_FIFO_STS 0x38
+#define REG_ADI_ARM_CMD_STS 0x3c
+#define REG_ADI_CHN_EN 0x40
+#define REG_ADI_CHN_ADDR(id) (0x44 + (id - 2) * 4)
+#define REG_ADI_CHN_EN1 0x20c
+
+/* Bits definitions for register REG_ADI_GSSI_CFG0 */
+#define BIT_CLK_ALL_ON BIT(30)
+
+/* Bits definitions for register REG_ADI_RD_DATA */
+#define BIT_RD_CMD_BUSY BIT(31)
+#define RD_ADDR_SHIFT 16
+#define RD_VALUE_MASK GENMASK(15, 0)
+#define RD_ADDR_MASK GENMASK(30, 16)
+
+/* Bits definitions for register REG_ADI_ARM_FIFO_STS */
+#define BIT_FIFO_FULL BIT(11)
+#define BIT_FIFO_EMPTY BIT(10)
+
+/*
+ * ADI slave devices include RTC, ADC, regulator, charger, thermal and so on.
+ * The slave devices address offset is always 0x8000 and size is 4K.
+ */
+#define ADI_SLAVE_ADDR_SIZE SZ_4K
+#define ADI_SLAVE_OFFSET 0x8000
+
+/* Timeout (ms) for the trylock of hardware spinlocks */
+#define ADI_HWSPINLOCK_TIMEOUT 5000
+/*
+ * ADI controller has 50 channels including 2 software channels
+ * and 48 hardware channels.
+ */
+#define ADI_HW_CHNS 50
+
+#define ADI_FIFO_DRAIN_TIMEOUT 1000
+#define ADI_READ_TIMEOUT 2000
+#define REG_ADDR_LOW_MASK GENMASK(11, 0)
+
+struct sprd_adi {
+ struct spi_controller *ctlr;
+ struct device *dev;
+ void __iomem *base;
+ struct hwspinlock *hwlock;
+ unsigned long slave_vbase;
+ unsigned long slave_pbase;
+};
+
+static int sprd_adi_check_paddr(struct sprd_adi *sadi, u32 paddr)
+{
+ if (paddr < sadi->slave_pbase || paddr >
+ (sadi->slave_pbase + ADI_SLAVE_ADDR_SIZE)) {
+ dev_err(sadi->dev,
+ "slave physical address is incorrect, addr = 0x%x\n",
+ paddr);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static unsigned long sprd_adi_to_vaddr(struct sprd_adi *sadi, u32 paddr)
+{
+ return (paddr - sadi->slave_pbase + sadi->slave_vbase);
+}
+
+static int sprd_adi_drain_fifo(struct sprd_adi *sadi)
+{
+ u32 timeout = ADI_FIFO_DRAIN_TIMEOUT;
+ u32 sts;
+
+ do {
+ sts = readl_relaxed(sadi->base + REG_ADI_ARM_FIFO_STS);
+ if (sts & BIT_FIFO_EMPTY)
+ break;
+
+ cpu_relax();
+ } while (--timeout);
+
+ if (timeout == 0) {
+ dev_err(sadi->dev, "drain write fifo timeout\n");
+ return -EBUSY;
+ }
+
+ return 0;
+}
+
+static int sprd_adi_fifo_is_full(struct sprd_adi *sadi)
+{
+ return readl_relaxed(sadi->base + REG_ADI_ARM_FIFO_STS) & BIT_FIFO_FULL;
+}
+
+static int sprd_adi_read(struct sprd_adi *sadi, u32 reg_paddr, u32 *read_val)
+{
+ int read_timeout = ADI_READ_TIMEOUT;
+ u32 val, rd_addr;
+
+ /*
+ * Set the physical register address need to read into RD_CMD register,
+ * then ADI controller will start to transfer automatically.
+ */
+ writel_relaxed(reg_paddr, sadi->base + REG_ADI_RD_CMD);
+
+ /*
+ * Wait read operation complete, the BIT_RD_CMD_BUSY will be set
+ * simultaneously when writing read command to register, and the
+ * BIT_RD_CMD_BUSY will be cleared after the read operation is
+ * completed.
+ */
+ do {
+ val = readl_relaxed(sadi->base + REG_ADI_RD_DATA);
+ if (!(val & BIT_RD_CMD_BUSY))
+ break;
+
+ cpu_relax();
+ } while (--read_timeout);
+
+ if (read_timeout == 0) {
+ dev_err(sadi->dev, "ADI read timeout\n");
+ return -EBUSY;
+ }
+
+ /*
+ * The return value includes data and read register address, from bit 0
+ * to bit 15 are data, and from bit 16 to bit 30 are read register
+ * address. Then we can check the returned register address to validate
+ * data.
+ */
+ rd_addr = (val & RD_ADDR_MASK ) >> RD_ADDR_SHIFT;
+
+ if (rd_addr != (reg_paddr & REG_ADDR_LOW_MASK)) {
+ dev_err(sadi->dev, "read error, reg addr = 0x%x, val = 0x%x\n",
+ reg_paddr, val);
+ return -EIO;
+ }
+
+ *read_val = val & RD_VALUE_MASK;
+ return 0;
+}
+
+static int sprd_adi_write(struct sprd_adi *sadi, unsigned long reg, u32 val)
+{
+ u32 timeout = ADI_FIFO_DRAIN_TIMEOUT;
+ int ret;
+
+ ret = sprd_adi_drain_fifo(sadi);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * we should wait for write fifo is empty before writing data to PMIC
+ * registers.
+ */
+ do {
+ if (!sprd_adi_fifo_is_full(sadi)) {
+ writel_relaxed(val, (void __iomem *)reg);
+ break;
+ }
+
+ cpu_relax();
+ } while (--timeout);
+
+ if (timeout == 0) {
+ dev_err(sadi->dev, "write fifo is full\n");
+ return -EBUSY;
+ }
+
+ return 0;
+}
+
+static int sprd_adi_transfer_one(struct spi_controller *ctlr,
+ struct spi_device *spi_dev,
+ struct spi_transfer *t)
+{
+ struct sprd_adi *sadi = spi_controller_get_devdata(ctlr);
+ unsigned long flags, virt_reg;
+ u32 phy_reg, val;
+ int ret;
+
+ if (t->rx_buf) {
+ phy_reg = *(u32 *)t->rx_buf + sadi->slave_pbase;
+
+ ret = sprd_adi_check_paddr(sadi, phy_reg);
+ if (ret)
+ return ret;
+
+ ret = hwspin_lock_timeout_irqsave(sadi->hwlock,
+ ADI_HWSPINLOCK_TIMEOUT,
+ &flags);
+ if (ret) {
+ dev_err(sadi->dev, "get the hw lock failed\n");
+ return ret;
+ }
+
+ ret = sprd_adi_read(sadi, phy_reg, &val);
+ hwspin_unlock_irqrestore(sadi->hwlock, &flags);
+ if (ret)
+ return ret;
+
+ *(u32 *)t->rx_buf = val;
+ } else if (t->tx_buf) {
+ u32 *p = (u32 *)t->tx_buf;
+
+ /*
+ * Get the physical register address need to write and convert
+ * the physical address to virtual address. Since we need
+ * virtual register address to write.
+ */
+ phy_reg = *p++ + sadi->slave_pbase;
+ ret = sprd_adi_check_paddr(sadi, phy_reg);
+ if (ret)
+ return ret;
+
+ virt_reg = sprd_adi_to_vaddr(sadi, phy_reg);
+ val = *p;
+
+ ret = hwspin_lock_timeout_irqsave(sadi->hwlock,
+ ADI_HWSPINLOCK_TIMEOUT,
+ &flags);
+ if (ret) {
+ dev_err(sadi->dev, "get the hw lock failed\n");
+ return ret;
+ }
+
+ ret = sprd_adi_write(sadi, virt_reg, val);
+ hwspin_unlock_irqrestore(sadi->hwlock, &flags);
+ if (ret)
+ return ret;
+ } else {
+ dev_err(sadi->dev, "no buffer for transfer\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static void sprd_adi_hw_init(struct sprd_adi *sadi)
+{
+ struct device_node *np = sadi->dev->of_node;
+ int i, size, chn_cnt;
+ const __be32 *list;
+ u32 tmp;
+
+ /* Address bits select default 12 bits */
+ writel_relaxed(0, sadi->base + REG_ADI_CTRL0);
+
+ /* Set all channels as default priority */
+ writel_relaxed(0, sadi->base + REG_ADI_CHN_PRIL);
+ writel_relaxed(0, sadi->base + REG_ADI_CHN_PRIH);
+
+ /* Set clock auto gate mode */
+ tmp = readl_relaxed(sadi->base + REG_ADI_GSSI_CFG0);
+ tmp &= ~BIT_CLK_ALL_ON;
+ writel_relaxed(tmp, sadi->base + REG_ADI_GSSI_CFG0);
+
+ /* Set hardware channels setting */
+ list = of_get_property(np, "sprd,hw-channels", &size);
+ if (!size || !list) {
+ dev_info(sadi->dev, "no hw channels setting in node\n");
+ return;
+ }
+
+ chn_cnt = size / 8;
+ for (i = 0; i < chn_cnt; i++) {
+ u32 value;
+ u32 chn_id = be32_to_cpu(*list++);
+ u32 chn_config = be32_to_cpu(*list++);
+
+ /* Channel 0 and 1 are software channels */
+ if (chn_id < 2)
+ continue;
+
+ writel_relaxed(chn_config, sadi->base +
+ REG_ADI_CHN_ADDR(chn_id));
+
+ if (chn_id < 31) {
+ value = readl_relaxed(sadi->base + REG_ADI_CHN_EN);
+ value |= BIT(chn_id);
+ writel_relaxed(value, sadi->base + REG_ADI_CHN_EN);
+ } else if (chn_id < ADI_HW_CHNS) {
+ value = readl_relaxed(sadi->base + REG_ADI_CHN_EN1);
+ value |= BIT(chn_id - 32);
+ writel_relaxed(value, sadi->base + REG_ADI_CHN_EN1);
+ }
+ }
+}
+
+static int sprd_adi_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct spi_controller *ctlr;
+ struct sprd_adi *sadi;
+ struct resource *res;
+ u32 num_chipselect;
+ int ret;
+
+ if (!np) {
+ dev_err(&pdev->dev, "can not find the adi bus node\n");
+ return -ENODEV;
+ }
+
+ pdev->id = of_alias_get_id(np, "spi");
+ num_chipselect = of_get_child_count(np);
+
+ ctlr = spi_alloc_master(&pdev->dev, sizeof(struct sprd_adi));
+ if (!ctlr)
+ return -ENOMEM;
+
+ dev_set_drvdata(&pdev->dev, ctlr);
+ sadi = spi_controller_get_devdata(ctlr);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ sadi->base = devm_ioremap_resource(&pdev->dev, res);
+ if (!sadi->base) {
+ ret = -ENOMEM;
+ goto put_ctlr;
+ }
+
+ sadi->slave_vbase = (unsigned long)sadi->base + ADI_SLAVE_OFFSET;
+ sadi->slave_pbase = res->start + ADI_SLAVE_OFFSET;
+ sadi->ctlr = ctlr;
+ sadi->dev = &pdev->dev;
+ ret = of_hwspin_lock_get_id(np, 0);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "can not get the hardware spinlock\n");
+ goto put_ctlr;
+ }
+
+ sadi->hwlock = hwspin_lock_request_specific(ret);
+ if (!sadi->hwlock) {
+ ret = -ENXIO;
+ goto put_ctlr;
+ }
+
+ sprd_adi_hw_init(sadi);
+
+ ctlr->dev.of_node = pdev->dev.of_node;
+ ctlr->bus_num = pdev->id;
+ ctlr->num_chipselect = num_chipselect;
+ ctlr->flags = SPI_MASTER_HALF_DUPLEX;
+ ctlr->bits_per_word_mask = 0;
+ ctlr->transfer_one = sprd_adi_transfer_one;
+
+ ret = devm_spi_register_controller(&pdev->dev, ctlr);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to register SPI controller\n");
+ goto free_hwlock;
+ }
+
+ return 0;
+
+free_hwlock:
+ hwspin_lock_free(sadi->hwlock);
+put_ctlr:
+ spi_controller_put(ctlr);
+ return ret;
+}
+
+static int sprd_adi_remove(struct platform_device *pdev)
+{
+ struct spi_controller *ctlr = dev_get_drvdata(&pdev->dev);
+ struct sprd_adi *sadi = spi_controller_get_devdata(ctlr);
+
+ hwspin_lock_free(sadi->hwlock);
+ return 0;
+}
+
+static const struct of_device_id sprd_adi_of_match[] = {
+ {
+ .compatible = "sprd,sc9860-adi",
+ },
+ { },
+};
+MODULE_DEVICE_TABLE(of, sprd_adi_of_match);
+
+static struct platform_driver sprd_adi_driver = {
+ .driver = {
+ .name = "sprd-adi",
+ .owner = THIS_MODULE,
+ .of_match_table = sprd_adi_of_match,
+ },
+ .probe = sprd_adi_probe,
+ .remove = sprd_adi_remove,
+};
+module_platform_driver(sprd_adi_driver);
+
+MODULE_DESCRIPTION("Spreadtrum ADI Controller Driver");
+MODULE_AUTHOR("Baolin Wang <[email protected]>");
+MODULE_LICENSE("GPL v2");
--
1.7.9.5
On Fri, Sep 15, 2017 at 03:29:15PM +0800, Baolin Wang wrote:
> This patch adds the binding documentation for Spreadtrum ADI
> controller device.
Please submit patches using subject lines reflecting the style for the
subsystem. This makes it easier for people to identify relevant
patches. Look at what existing commits in the area you're changing are
doing and make sure your subject lines visually resemble what they're
doing.
On Fri, Sep 15, 2017 at 03:29:15PM +0800, Baolin Wang wrote:
> This patch adds the binding documentation for Spreadtrum ADI
> controller device.
>
> Signed-off-by: Baolin Wang <[email protected]>
> ---
> Changes since v2:
> - Add some documentation to describe how many hardware channels can be
> configured.
> - Remove "SPI framework" from binding file and other small optimization.
>
> Changes since v1:
> - Add more documentation for the 'sprd,hw-channels' property and explain
> why need one hardware spinlock.
> ---
> .../devicetree/bindings/spi/spi-sprd-adi.txt | 58 ++++++++++++++++++++
> 1 file changed, 58 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/spi/spi-sprd-adi.txt
Acked-by: Rob Herring <[email protected]>