drivers: spmi: Add support for Qualcomm SPMI bus driver

[u-boot] / drivers / spmi / spmi-msm.c

diff --git a/drivers/spmi/spmi-msm.c b/drivers/spmi/spmi-msm.c
new file mode 100644 (file)
index 0000000..0cef505
--- /dev/null
+++ b/drivers/spmi/spmi-msm.c
@@ -0,0 +1,189 @@
+/*
+ * Qualcomm SPMI bus driver
+ *
+ * (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
+ *
+ * Loosely based on Little Kernel driver
+ *
+ * SPDX-License-Identifier:    BSD-3-Clause
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <fdtdec.h>
+#include <asm/io.h>
+#include <spmi/spmi.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define ARB_CHANNEL_OFFSET(n)          (0x4 * (n))
+#define SPMI_CH_OFFSET(chnl)           ((chnl) * 0x8000)
+
+#define SPMI_REG_CMD0                  0x0
+#define SPMI_REG_CONFIG                        0x4
+#define SPMI_REG_STATUS                        0x8
+#define SPMI_REG_WDATA                 0x10
+#define SPMI_REG_RDATA                 0x18
+
+#define SPMI_CMD_OPCODE_SHIFT          27
+#define SPMI_CMD_SLAVE_ID_SHIFT                20
+#define SPMI_CMD_ADDR_SHIFT            12
+#define SPMI_CMD_ADDR_OFFSET_SHIFT     4
+#define SPMI_CMD_BYTE_CNT_SHIFT                0
+
+#define SPMI_CMD_EXT_REG_WRITE_LONG    0x00
+#define SPMI_CMD_EXT_REG_READ_LONG     0x01
+
+#define SPMI_STATUS_DONE               0x1
+
+#define SPMI_MAX_CHANNELS      128
+#define SPMI_MAX_SLAVES                16
+#define SPMI_MAX_PERIPH                256
+
+struct msm_spmi_priv {
+       phys_addr_t arb_chnl; /* ARB channel mapping base */
+       phys_addr_t spmi_core; /* SPMI core */
+       phys_addr_t spmi_obs; /* SPMI observer */
+       /* SPMI channel map */
+       uint8_t channel_map[SPMI_MAX_SLAVES][SPMI_MAX_PERIPH];
+};
+
+static int msm_spmi_write(struct udevice *dev, int usid, int pid, int off,
+                         uint8_t val)
+{
+       struct msm_spmi_priv *priv = dev_get_priv(dev);
+       unsigned channel;
+       uint32_t reg = 0;
+
+       if (usid >= SPMI_MAX_SLAVES)
+               return -EIO;
+       if (pid >= SPMI_MAX_PERIPH)
+               return -EIO;
+
+       channel = priv->channel_map[usid][pid];
+
+       /* Disable IRQ mode for the current channel*/
+       writel(0x0, priv->spmi_core + SPMI_CH_OFFSET(channel) +
+              SPMI_REG_CONFIG);
+
+       /* Write single byte */
+       writel(val, priv->spmi_core + SPMI_CH_OFFSET(channel) + SPMI_REG_WDATA);
+
+       /* Prepare write command */
+       reg |= SPMI_CMD_EXT_REG_WRITE_LONG << SPMI_CMD_OPCODE_SHIFT;
+       reg |= (usid << SPMI_CMD_SLAVE_ID_SHIFT);
+       reg |= (pid << SPMI_CMD_ADDR_SHIFT);
+       reg |= (off << SPMI_CMD_ADDR_OFFSET_SHIFT);
+       reg |= 1; /* byte count */
+
+       /* Send write command */
+       writel(reg, priv->spmi_core + SPMI_CH_OFFSET(channel) + SPMI_REG_CMD0);
+
+       /* Wait till CMD DONE status */
+       reg = 0;
+       while (!reg) {
+               reg = readl(priv->spmi_core + SPMI_CH_OFFSET(channel) +
+                           SPMI_REG_STATUS);
+       }
+
+       if (reg ^ SPMI_STATUS_DONE) {
+               printf("SPMI write failure.\n");
+               return -EIO;
+       }
+
+       return 0;
+}
+
+static int msm_spmi_read(struct udevice *dev, int usid, int pid, int off)
+{
+       struct msm_spmi_priv *priv = dev_get_priv(dev);
+       unsigned channel;
+       uint32_t reg = 0;
+
+       if (usid >= SPMI_MAX_SLAVES)
+               return -EIO;
+       if (pid >= SPMI_MAX_PERIPH)
+               return -EIO;
+
+       channel = priv->channel_map[usid][pid];
+
+       /* Disable IRQ mode for the current channel*/
+       writel(0x0, priv->spmi_obs + SPMI_CH_OFFSET(channel) + SPMI_REG_CONFIG);
+
+       /* Prepare read command */
+       reg |= SPMI_CMD_EXT_REG_READ_LONG << SPMI_CMD_OPCODE_SHIFT;
+       reg |= (usid << SPMI_CMD_SLAVE_ID_SHIFT);
+       reg |= (pid << SPMI_CMD_ADDR_SHIFT);
+       reg |= (off << SPMI_CMD_ADDR_OFFSET_SHIFT);
+       reg |= 1; /* byte count */
+
+       /* Request read */
+       writel(reg, priv->spmi_obs + SPMI_CH_OFFSET(channel) + SPMI_REG_CMD0);
+
+       /* Wait till CMD DONE status */
+       reg = 0;
+       while (!reg) {
+               reg = readl(priv->spmi_obs + SPMI_CH_OFFSET(channel) +
+                           SPMI_REG_STATUS);
+       }
+
+       if (reg ^ SPMI_STATUS_DONE) {
+               printf("SPMI read failure.\n");
+               return -EIO;
+       }
+
+       /* Read the data */
+       return readl(priv->spmi_obs + SPMI_CH_OFFSET(channel) +
+                    SPMI_REG_RDATA) & 0xFF;
+}
+
+static struct dm_spmi_ops msm_spmi_ops = {
+       .read = msm_spmi_read,
+       .write = msm_spmi_write,
+};
+
+static int msm_spmi_probe(struct udevice *dev)
+{
+       struct udevice *parent = dev->parent;
+       struct msm_spmi_priv *priv = dev_get_priv(dev);
+       int i;
+
+       priv->arb_chnl = dev_get_addr(dev);
+       priv->spmi_core = fdtdec_get_addr_size_auto_parent(gd->fdt_blob,
+                                                          parent->of_offset,
+                                                          dev->of_offset,
+                                                          "reg", 1, NULL);
+       priv->spmi_obs = fdtdec_get_addr_size_auto_parent(gd->fdt_blob,
+                                                         parent->of_offset,
+                                                         dev->of_offset, "reg",
+                                                         2, NULL);
+       if (priv->arb_chnl == FDT_ADDR_T_NONE ||
+           priv->spmi_core == FDT_ADDR_T_NONE ||
+           priv->spmi_obs == FDT_ADDR_T_NONE)
+               return -EINVAL;
+
+       /* Scan peripherals connected to each SPMI channel */
+       for (i = 0; i < SPMI_MAX_CHANNELS ; i++) {
+               uint32_t periph = readl(priv->arb_chnl + ARB_CHANNEL_OFFSET(i));
+               uint8_t slave_id = (periph & 0xf0000) >> 16;
+               uint8_t pid = (periph & 0xff00) >> 8;
+
+               priv->channel_map[slave_id][pid] = i;
+       }
+       return 0;
+}
+
+static const struct udevice_id msm_spmi_ids[] = {
+       { .compatible = "qcom,spmi-pmic-arb" },
+       { }
+};
+
+U_BOOT_DRIVER(msm_spmi) = {
+       .name = "msm_spmi",
+       .id = UCLASS_SPMI,
+       .of_match = msm_spmi_ids,
+       .ops = &msm_spmi_ops,
+       .probe = msm_spmi_probe,
+       .priv_auto_alloc_size = sizeof(struct msm_spmi_priv),
+};