diff mbox series

[net-next,v2,1/3] net: dsa: microchip: add KSZ9477 I2C driver

Message ID 20190910131836.114058-2-george.mccollister@gmail.com
State Accepted
Delegated to: David Miller
Headers show
Series add ksz9567 with I2C support to ksz9477 driver | expand

Commit Message

George McCollister Sept. 10, 2019, 1:18 p.m. UTC 
From: Tristram Ha <Tristram.Ha@microchip.com>

Add KSZ9477 I2C driver support.  The code ksz9477.c and ksz_common.c are
used together to generate the I2C driver.

Signed-off-by: Tristram Ha <Tristram.Ha@microchip.com>
[george.mccollister@gmail.com: bring up to date, use ksz_common regmap macros]
Signed-off-by: George McCollister <george.mccollister@gmail.com>
---

Changes since v1:
	- Adjust order of includes so they are in alphabetical order.

 drivers/net/dsa/microchip/Kconfig       |   7 +++
 drivers/net/dsa/microchip/Makefile      |   1 +
 drivers/net/dsa/microchip/ksz9477_i2c.c | 100 ++++++++++++++++++++++++++++++++
 drivers/net/dsa/microchip/ksz_common.h  |   2 +
 4 files changed, 110 insertions(+)
 create mode 100644 drivers/net/dsa/microchip/ksz9477_i2c.c

Comments

Andrew Lunn Sept. 10, 2019, 2:03 p.m. UTC | #1 
Hi George

> +KSZ_REGMAP_TABLE(ksz9477, not_used, 16, 0, 0);
> +
> @@ -294,6 +294,8 @@ static inline void ksz_pwrite32(struct ksz_device *dev, int port, int offset,
>  #define KSZ_SPI_OP_RD		3
>  #define KSZ_SPI_OP_WR		2
>  
> +#define swabnot_used(x)		0

> +
>  #define KSZ_SPI_OP_FLAG_MASK(opcode, swp, regbits, regpad)		\
>  	swab##swp((opcode) << ((regbits) + (regpad)))

There seems to be quite a lot of macro magic here which is not
obvious. Can this be simplified or made more obvious?

	 Andrew
George McCollister Sept. 10, 2019, 2:40 p.m. UTC | #2 
Andrew,

On Tue, Sep 10, 2019 at 9:03 AM Andrew Lunn <andrew@lunn.ch> wrote:
>
> Hi George
>
> > +KSZ_REGMAP_TABLE(ksz9477, not_used, 16, 0, 0);
> > +
> > @@ -294,6 +294,8 @@ static inline void ksz_pwrite32(struct ksz_device *dev, int port, int offset,
> >  #define KSZ_SPI_OP_RD                3
> >  #define KSZ_SPI_OP_WR                2
> >
> > +#define swabnot_used(x)              0
>
> > +
> >  #define KSZ_SPI_OP_FLAG_MASK(opcode, swp, regbits, regpad)           \
> >       swab##swp((opcode) << ((regbits) + (regpad)))
>
> There seems to be quite a lot of macro magic here which is not
> obvious. Can this be simplified or made more obvious?

I thought about this for quite some time. To reduce the "macro magic"
the SPI specific parts will need to be removed from the common macro
and arguments for read_flag_mask and write_flag_mask would need to be
added to both KSZ_REGMAP_TABLE and KSZ_REGMAP_TABLE. That would leave
us with two macros that have 7 arguments. Not really an improvement
IMHO. Alternatively we could have different macros for SPI and I2C (or
not use the macros at all and define the i2c regmaps in ksz9477_i2c.c)
at the cost of ~20 lines of duplication. I prefer the "macro magic"
approach, however if you won't let the patch through the way it is
I'll respect your decision, just let me know which of the three
proposed approaches you want to go with.

>
>          Andrew

Cheers,
George
diff mbox series

Patch

diff --git a/drivers/net/dsa/microchip/Kconfig b/drivers/net/dsa/microchip/Kconfig
index e1c23d1e91e6..1d7870c6df3c 100644
--- a/drivers/net/dsa/microchip/Kconfig
+++ b/drivers/net/dsa/microchip/Kconfig
@@ -9,6 +9,13 @@  menuconfig NET_DSA_MICROCHIP_KSZ9477
 	help
 	  This driver adds support for Microchip KSZ9477 switch chips.
 
+config NET_DSA_MICROCHIP_KSZ9477_I2C
+	tristate "KSZ9477 series I2C connected switch driver"
+	depends on NET_DSA_MICROCHIP_KSZ9477 && I2C
+	select REGMAP_I2C
+	help
+	  Select to enable support for registering switches configured through I2C.
+
 config NET_DSA_MICROCHIP_KSZ9477_SPI
 	tristate "KSZ9477 series SPI connected switch driver"
 	depends on NET_DSA_MICROCHIP_KSZ9477 && SPI
diff --git a/drivers/net/dsa/microchip/Makefile b/drivers/net/dsa/microchip/Makefile
index e3d799b95d7d..929caa81e782 100644
--- a/drivers/net/dsa/microchip/Makefile
+++ b/drivers/net/dsa/microchip/Makefile
@@ -1,6 +1,7 @@ 
 # SPDX-License-Identifier: GPL-2.0-only
 obj-$(CONFIG_NET_DSA_MICROCHIP_KSZ_COMMON)	+= ksz_common.o
 obj-$(CONFIG_NET_DSA_MICROCHIP_KSZ9477)		+= ksz9477.o
+obj-$(CONFIG_NET_DSA_MICROCHIP_KSZ9477_I2C)	+= ksz9477_i2c.o
 obj-$(CONFIG_NET_DSA_MICROCHIP_KSZ9477_SPI)	+= ksz9477_spi.o
 obj-$(CONFIG_NET_DSA_MICROCHIP_KSZ8795)		+= ksz8795.o
 obj-$(CONFIG_NET_DSA_MICROCHIP_KSZ8795_SPI)	+= ksz8795_spi.o
diff --git a/drivers/net/dsa/microchip/ksz9477_i2c.c b/drivers/net/dsa/microchip/ksz9477_i2c.c
new file mode 100644
index 000000000000..79867cc2474b
--- /dev/null
+++ b/drivers/net/dsa/microchip/ksz9477_i2c.c
@@ -0,0 +1,100 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Microchip KSZ9477 series register access through I2C
+ *
+ * Copyright (C) 2018-2019 Microchip Technology Inc.
+ */
+
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+
+#include "ksz_common.h"
+
+KSZ_REGMAP_TABLE(ksz9477, not_used, 16, 0, 0);
+
+static int ksz9477_i2c_probe(struct i2c_client *i2c,
+			     const struct i2c_device_id *i2c_id)
+{
+	struct ksz_device *dev;
+	int i, ret;
+
+	dev = ksz_switch_alloc(&i2c->dev, i2c);
+	if (!dev)
+		return -ENOMEM;
+
+	for (i = 0; i < ARRAY_SIZE(ksz9477_regmap_config); i++) {
+		dev->regmap[i] = devm_regmap_init_i2c(i2c,
+					&ksz9477_regmap_config[i]);
+		if (IS_ERR(dev->regmap[i])) {
+			ret = PTR_ERR(dev->regmap[i]);
+			dev_err(&i2c->dev,
+				"Failed to initialize regmap%i: %d\n",
+				ksz9477_regmap_config[i].val_bits, ret);
+			return ret;
+		}
+	}
+
+	if (i2c->dev.platform_data)
+		dev->pdata = i2c->dev.platform_data;
+
+	ret = ksz9477_switch_register(dev);
+
+	/* Main DSA driver may not be started yet. */
+	if (ret)
+		return ret;
+
+	i2c_set_clientdata(i2c, dev);
+
+	return 0;
+}
+
+static int ksz9477_i2c_remove(struct i2c_client *i2c)
+{
+	struct ksz_device *dev = i2c_get_clientdata(i2c);
+
+	ksz_switch_remove(dev);
+
+	return 0;
+}
+
+static void ksz9477_i2c_shutdown(struct i2c_client *i2c)
+{
+	struct ksz_device *dev = i2c_get_clientdata(i2c);
+
+	if (dev && dev->dev_ops->shutdown)
+		dev->dev_ops->shutdown(dev);
+}
+
+static const struct i2c_device_id ksz9477_i2c_id[] = {
+	{ "ksz9477-switch", 0 },
+	{},
+};
+
+MODULE_DEVICE_TABLE(i2c, ksz9477_i2c_id);
+
+static const struct of_device_id ksz9477_dt_ids[] = {
+	{ .compatible = "microchip,ksz9477" },
+	{ .compatible = "microchip,ksz9897" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, ksz9477_dt_ids);
+
+static struct i2c_driver ksz9477_i2c_driver = {
+	.driver = {
+		.name	= "ksz9477-switch",
+		.owner	= THIS_MODULE,
+		.of_match_table = of_match_ptr(ksz9477_dt_ids),
+	},
+	.probe	= ksz9477_i2c_probe,
+	.remove	= ksz9477_i2c_remove,
+	.shutdown = ksz9477_i2c_shutdown,
+	.id_table = ksz9477_i2c_id,
+};
+
+module_i2c_driver(ksz9477_i2c_driver);
+
+MODULE_AUTHOR("Tristram Ha <Tristram.Ha@microchip.com>");
+MODULE_DESCRIPTION("Microchip KSZ9477 Series Switch I2C access Driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/net/dsa/microchip/ksz_common.h b/drivers/net/dsa/microchip/ksz_common.h
index 13d027baaa8b..a24d8e61fbe7 100644
--- a/drivers/net/dsa/microchip/ksz_common.h
+++ b/drivers/net/dsa/microchip/ksz_common.h
@@ -294,6 +294,8 @@  static inline void ksz_pwrite32(struct ksz_device *dev, int port, int offset,
 #define KSZ_SPI_OP_RD		3
 #define KSZ_SPI_OP_WR		2
 
+#define swabnot_used(x)		0
+
 #define KSZ_SPI_OP_FLAG_MASK(opcode, swp, regbits, regpad)		\
 	swab##swp((opcode) << ((regbits) + (regpad)))