drivers: Add SPMI bus uclass

Qualcom processors use proprietary bus to talk with PMIC devices -
SPMI (System Power Management Interface).
On wiring level it is similar to I2C, but on protocol level, it's
multi-master and has simple autodetection capabilities.
This commit adds simple uclass that provides bus read/write interface.

Signed-off-by: Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>

diff --git a/drivers/Kconfig b/drivers/Kconfig
index 70993fdab80f2e0985bcc802de695d9076fd28b4..c82a94b7a50ca7272cca672cd64e052d09792ee1 100644 (file)
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -60,6 +60,8 @@ source "drivers/sound/Kconfig"
 
 source "drivers/spi/Kconfig"
 
+source "drivers/spmi/Kconfig"
+
 source "drivers/thermal/Kconfig"
 
 source "drivers/timer/Kconfig"

diff --git a/drivers/Makefile b/drivers/Makefile
index e7eab6603e05fc104e101385f1ffa285003e04f0..6900097e79986785d3d6f1e4691f9614780073ff 100644 (file)
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -54,6 +54,7 @@ obj-y += dfu/
 obj-$(CONFIG_X86) += pch/
 obj-y += rtc/
 obj-y += sound/
+obj-y += spmi/
 obj-y += timer/
 obj-y += tpm/
 obj-y += twserial/

diff --git a/drivers/spmi/Kconfig b/drivers/spmi/Kconfig
new file mode 100644 (file)
index 0000000..0b9bd31
--- /dev/null
+++ b/drivers/spmi/Kconfig
@@ -0,0 +1,10 @@
+menu "SPMI support"
+
+config SPMI
+       bool "Enable SPMI bus support"
+       depends on DM
+       ---help---
+         Select this to enable to support SPMI bus.
+         SPMI (System Power Management Interface) bus is used
+         to connect PMIC devices on various SoCs.
+endmenu

diff --git a/drivers/spmi/Makefile b/drivers/spmi/Makefile
new file mode 100644 (file)
index 0000000..99092eb
--- /dev/null
+++ b/drivers/spmi/Makefile
@@ -0,0 +1,7 @@
+#
+# (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
+#
+# SPDX-License-Identifier:     GPL-2.0+
+#
+
+obj-$(CONFIG_SPMI)  += spmi-uclass.o

diff --git a/drivers/spmi/spmi-uclass.c b/drivers/spmi/spmi-uclass.c
new file mode 100644 (file)
index 0000000..4ddd51b
--- /dev/null
+++ b/drivers/spmi/spmi-uclass.c
@@ -0,0 +1,48 @@
+/*
+ * SPMI bus uclass driver
+ *
+ * (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
+ *
+ * SPDX-License-Identifier:    GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <dm/root.h>
+#include <spmi/spmi.h>
+#include <linux/ctype.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+int spmi_reg_read(struct udevice *dev, int usid, int pid, int reg)
+{
+       const struct dm_spmi_ops *ops = dev_get_driver_ops(dev);
+
+       if (!ops || !ops->read)
+               return -ENOSYS;
+
+       return ops->read(dev, usid, pid, reg);
+}
+
+int spmi_reg_write(struct udevice *dev, int usid, int pid, int reg,
+                  uint8_t value)
+{
+       const struct dm_spmi_ops *ops = dev_get_driver_ops(dev);
+
+       if (!ops || !ops->write)
+               return -ENOSYS;
+
+       return ops->write(dev, usid, pid, reg, value);
+}
+
+static int spmi_post_bind(struct udevice *dev)
+{
+       return dm_scan_fdt_node(dev, gd->fdt_blob, dev->of_offset, false);
+}
+
+UCLASS_DRIVER(spmi) = {
+       .id             = UCLASS_SPMI,
+       .name           = "spmi",
+       .post_bind      = spmi_post_bind,
+};

diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h
index 37c4176d5787a5854a41300e62cf769dd25fb638..cbf9b2ca235190714b81fc1c07460d997e5e95d5 100644 (file)
--- a/include/dm/uclass-id.h
+++ b/include/dm/uclass-id.h
@@ -66,6 +66,7 @@ enum uclass_id {
        UCLASS_RTC,             /* Real time clock device */
        UCLASS_SERIAL,          /* Serial UART */
        UCLASS_SPI,             /* SPI bus */
+       UCLASS_SPMI,            /* System Power Management Interface bus */
        UCLASS_SPI_FLASH,       /* SPI flash */
        UCLASS_SPI_GENERIC,     /* Generic SPI flash target */
        UCLASS_SYSCON,          /* System configuration device */

diff --git a/include/spmi/spmi.h b/include/spmi/spmi.h
new file mode 100644 (file)
index 0000000..3242e6b
--- /dev/null
+++ b/include/spmi/spmi.h
@@ -0,0 +1,46 @@
+#ifndef _SPMI_SPMI_H
+#define _SPMI_SPMI_H
+
+/**
+ * struct dm_spmi_ops - SPMI device I/O interface
+ *
+ * Should be implemented by UCLASS_SPMI device drivers. The standard
+ * device operations provides the I/O interface for it's childs.
+ *
+ * @read:      read register 'reg' of slave 'usid' and peripheral 'pid'
+ * @write:     write register 'reg' of slave 'usid' and peripheral 'pid'
+ *
+ * Each register is 8-bit, both read and write can return negative values
+ * on error.
+ */
+struct dm_spmi_ops {
+       int (*read)(struct udevice *dev, int usid, int pid, int reg);
+       int (*write)(struct udevice *dev, int usid, int pid, int reg,
+                    uint8_t value);
+};
+
+/**
+ * spmi_reg_read() - read a register from specific slave/peripheral
+ *
+ * @dev:       SPMI bus to read
+ * @usid       SlaveID
+ * @pid                Peripheral ID
+ * @reg:       Register to read
+ * @return value read on success or negative value of errno.
+ */
+int spmi_reg_read(struct udevice *dev, int usid, int pid, int reg);
+
+/**
+ * spmi_reg_write() - write a register of specific slave/peripheral
+ *
+ * @dev:       SPMI bus to write
+ * @usid       SlaveID
+ * @pid                Peripheral ID
+ * @reg:       Register to write
+ * @value:     Value to write
+ * @return 0 on success or negative value of errno.
+ */
+int spmi_reg_write(struct udevice *dev, int usid, int pid, int reg,
+                  uint8_t value);
+
+#endif