[PATCH v3 1/3] i3c: dw: Add infrastructure for platform-specific implementations
Jeremy Kerr
jk at codeconstruct.com.au
Fri Mar 31 20:14:59 AEDT 2023
The dw i3c core can be integrated into various SoC devices. Platforms
that use this core may need a little configuration that is specific to
that platform.
Add some infrastructure to allow platform-specific behaviour: common
probe/remove functions, a set of platform hook operations, and a pointer
for platform-specific data in struct dw_i3c_master. Move the common api
into a new (i3c local) header file.
Platforms will provide their own struct platform_driver, which allocates
struct dw_i3c_master, does any platform-specific probe behaviour, and
calls into the common probe.
A future change will add new platform support that uses this
infrastructure.
Signed-off-by: Jeremy Kerr <jk at codeconstruct.com.au>
---
v2:
- structure for platform implementations as separate platform_drivers,
to be implemented in separate source files
- provide default ops rather than null checks
v3:
- remove ->platform_data to use an encapsulated dw_i3c_master
for platform implementations instead
---
drivers/i3c/master/dw-i3c-master.c | 76 +++++++++++++++++-------------
drivers/i3c/master/dw-i3c-master.h | 54 +++++++++++++++++++++
2 files changed, 97 insertions(+), 33 deletions(-)
create mode 100644 drivers/i3c/master/dw-i3c-master.h
diff --git a/drivers/i3c/master/dw-i3c-master.c b/drivers/i3c/master/dw-i3c-master.c
index 1c146a39e1bd..9fc03108a5db 100644
--- a/drivers/i3c/master/dw-i3c-master.c
+++ b/drivers/i3c/master/dw-i3c-master.c
@@ -21,6 +21,8 @@
#include <linux/reset.h>
#include <linux/slab.h>
+#include "dw-i3c-master.h"
+
#define DEVICE_CTRL 0x0
#define DEV_CTRL_ENABLE BIT(31)
#define DEV_CTRL_RESUME BIT(30)
@@ -189,8 +191,6 @@
#define DEV_ADDR_TABLE_STATIC_ADDR(x) ((x) & GENMASK(6, 0))
#define DEV_ADDR_TABLE_LOC(start, idx) ((start) + ((idx) << 2))
-#define MAX_DEVS 32
-
#define I3C_BUS_SDR1_SCL_RATE 8000000
#define I3C_BUS_SDR2_SCL_RATE 6000000
#define I3C_BUS_SDR3_SCL_RATE 4000000
@@ -201,11 +201,6 @@
#define XFER_TIMEOUT (msecs_to_jiffies(1000))
-struct dw_i3c_master_caps {
- u8 cmdfifodepth;
- u8 datafifodepth;
-};
-
struct dw_i3c_cmd {
u32 cmd_lo;
u32 cmd_hi;
@@ -224,25 +219,6 @@ struct dw_i3c_xfer {
struct dw_i3c_cmd cmds[];
};
-struct dw_i3c_master {
- struct i3c_master_controller base;
- u16 maxdevs;
- u16 datstartaddr;
- u32 free_pos;
- struct {
- struct list_head list;
- struct dw_i3c_xfer *cur;
- spinlock_t lock;
- } xferqueue;
- struct dw_i3c_master_caps caps;
- void __iomem *regs;
- struct reset_control *core_rst;
- struct clk *core_clk;
- char version[5];
- char type[5];
- u8 addrs[MAX_DEVS];
-};
-
struct dw_i3c_i2c_dev_data {
u8 index;
};
@@ -602,6 +578,10 @@ static int dw_i3c_master_bus_init(struct i3c_master_controller *m)
u32 thld_ctrl;
int ret;
+ ret = master->platform_ops->init(master);
+ if (ret)
+ return ret;
+
switch (bus->mode) {
case I3C_BUS_MODE_MIXED_FAST:
case I3C_BUS_MODE_MIXED_LIMITED:
@@ -1124,14 +1104,23 @@ static const struct i3c_master_controller_ops dw_mipi_i3c_ops = {
.i2c_xfers = dw_i3c_master_i2c_xfers,
};
-static int dw_i3c_probe(struct platform_device *pdev)
+/* default platform ops implementations */
+static int dw_i3c_platform_init_nop(struct dw_i3c_master *i3c)
+{
+ return 0;
+}
+
+static const struct dw_i3c_platform_ops dw_i3c_platform_ops_default = {
+ .init = dw_i3c_platform_init_nop,
+};
+
+int dw_i3c_common_probe(struct dw_i3c_master *master,
+ struct platform_device *pdev)
{
- struct dw_i3c_master *master;
int ret, irq;
- master = devm_kzalloc(&pdev->dev, sizeof(*master), GFP_KERNEL);
- if (!master)
- return -ENOMEM;
+ if (!master->platform_ops)
+ master->platform_ops = &dw_i3c_platform_ops_default;
master->regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(master->regs))
@@ -1192,10 +1181,10 @@ static int dw_i3c_probe(struct platform_device *pdev)
return ret;
}
+EXPORT_SYMBOL_GPL(dw_i3c_common_probe);
-static int dw_i3c_remove(struct platform_device *pdev)
+int dw_i3c_common_remove(struct dw_i3c_master *master)
{
- struct dw_i3c_master *master = platform_get_drvdata(pdev);
int ret;
ret = i3c_master_unregister(&master->base);
@@ -1208,6 +1197,27 @@ static int dw_i3c_remove(struct platform_device *pdev)
return 0;
}
+EXPORT_SYMBOL_GPL(dw_i3c_common_remove);
+
+/* base platform implementation */
+
+static int dw_i3c_probe(struct platform_device *pdev)
+{
+ struct dw_i3c_master *master;
+
+ master = devm_kzalloc(&pdev->dev, sizeof(*master), GFP_KERNEL);
+ if (!master)
+ return -ENOMEM;
+
+ return dw_i3c_common_probe(master, pdev);
+}
+
+static int dw_i3c_remove(struct platform_device *pdev)
+{
+ struct dw_i3c_master *master = platform_get_drvdata(pdev);
+
+ return dw_i3c_common_remove(master);
+}
static const struct of_device_id dw_i3c_master_of_match[] = {
{ .compatible = "snps,dw-i3c-master-1.00a", },
diff --git a/drivers/i3c/master/dw-i3c-master.h b/drivers/i3c/master/dw-i3c-master.h
new file mode 100644
index 000000000000..cd376daa28cf
--- /dev/null
+++ b/drivers/i3c/master/dw-i3c-master.h
@@ -0,0 +1,54 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2023 Code Construct
+ *
+ * Author: Jeremy Kerr <jk at codeconstruct.com.au>
+ */
+
+#include <linux/clk.h>
+#include <linux/i3c/master.h>
+#include <linux/reset.h>
+#include <linux/types.h>
+
+#define DW_I3C_MAX_DEVS 32
+
+struct dw_i3c_master_caps {
+ u8 cmdfifodepth;
+ u8 datafifodepth;
+};
+
+struct dw_i3c_master {
+ struct i3c_master_controller base;
+ u16 maxdevs;
+ u16 datstartaddr;
+ u32 free_pos;
+ struct {
+ struct list_head list;
+ struct dw_i3c_xfer *cur;
+ spinlock_t lock;
+ } xferqueue;
+ struct dw_i3c_master_caps caps;
+ void __iomem *regs;
+ struct reset_control *core_rst;
+ struct clk *core_clk;
+ char version[5];
+ char type[5];
+ u8 addrs[DW_I3C_MAX_DEVS];
+
+ /* platform-specific data */
+ const struct dw_i3c_platform_ops *platform_ops;
+};
+
+struct dw_i3c_platform_ops {
+ /*
+ * Called on early bus init: the i3c has been set up, but before any
+ * transactions have taken place. Platform implementations may use to
+ * perform actual device enabling with the i3c core ready.
+ */
+ int (*init)(struct dw_i3c_master *i3c);
+};
+
+extern int dw_i3c_common_probe(struct dw_i3c_master *master,
+ struct platform_device *pdev);
+extern int dw_i3c_common_remove(struct dw_i3c_master *master);
+
--
2.39.1
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