[PATCH v2 0/4] net: dsa: Add Vitesse VSC73xx parallel mode

[PATCH v2 0/4] net: dsa: Add Vitesse VSC73xx parallel mode

[Pawel Dembicki]

Main goal of this patch series is to add support for parallel bus in
Vitesse VSC73xx switches. Existing driver supports only SPI mode.

Second change is needed for devices in unmanaged state.

V2:
- drop changes in compatible strings
- make changes less invasive
- drop mutex in platform part and move mutex from core to spi part
- fix indentation 
- fix devm_ioremap_resource result check
- add cover letter 

Pawel Dembicki (4):
  net: dsa: Change DT bindings for Vitesse VSC73xx switches
  net: dsa: vsc73xx: Split vsc73xx driver
  net: dsa: vsc73xx: add support for parallel mode
  net: dsa: vsc73xx: Assert reset if iCPU is enabled

 .../bindings/net/dsa/vitesse,vsc73xx.txt      |  57 ++++-
 drivers/net/dsa/Kconfig                       |  19 +-
 drivers/net/dsa/Makefile                      |   4 +-
 ...tesse-vsc73xx.c => vitesse-vsc73xx-core.c} | 206 +++---------------
 drivers/net/dsa/vitesse-vsc73xx-platform.c    | 160 ++++++++++++++
 drivers/net/dsa/vitesse-vsc73xx-spi.c         | 203 +++++++++++++++++
 drivers/net/dsa/vitesse-vsc73xx.h             |  29 +++
 7 files changed, 493 insertions(+), 185 deletions(-)
 rename drivers/net/dsa/{vitesse-vsc73xx.c => vitesse-vsc73xx-core.c} (90%)
 create mode 100644 drivers/net/dsa/vitesse-vsc73xx-platform.c
 create mode 100644 drivers/net/dsa/vitesse-vsc73xx-spi.c
 create mode 100644 drivers/net/dsa/vitesse-vsc73xx.h

-- 
2.20.1

[PATCH v2 1/4] net: dsa: Change DT bindings for Vitesse VSC73xx switches

[Pawel Dembicki]

This commit introduce how to use vsc73xx platform driver.

Signed-off-by: Pawel Dembicki <paweldembicki@gmail.com>
---
 .../bindings/net/dsa/vitesse,vsc73xx.txt      | 57 +++++++++++++++++--
 1 file changed, 53 insertions(+), 4 deletions(-)

diff --git a/Documentation/devicetree/bindings/net/dsa/vitesse,vsc73xx.txt b/Documentation/devicetree/bindings/net/dsa/vitesse,vsc73xx.txt
index ed4710c40641..c55e0148657d 100644
--- a/Documentation/devicetree/bindings/net/dsa/vitesse,vsc73xx.txt
+++ b/Documentation/devicetree/bindings/net/dsa/vitesse,vsc73xx.txt
@@ -2,8 +2,8 @@ Vitesse VSC73xx Switches
 ========================
 
 This defines device tree bindings for the Vitesse VSC73xx switch chips.
-The Vitesse company has been acquired by Microsemi and Microsemi in turn
-acquired by Microchip but retains this vendor branding.
+The Vitesse company has been acquired by Microsemi and Microsemi has
+been acquired Microchip but retains this vendor branding.
 
 The currently supported switch chips are:
 Vitesse VSC7385 SparX-G5 5+1-port Integrated Gigabit Ethernet Switch
@@ -11,8 +11,13 @@ Vitesse VSC7388 SparX-G8 8-port Integrated Gigabit Ethernet Switch
 Vitesse VSC7395 SparX-G5e 5+1-port Integrated Gigabit Ethernet Switch
 Vitesse VSC7398 SparX-G8e 8-port Integrated Gigabit Ethernet Switch
 
-The device tree node is an SPI device so it must reside inside a SPI bus
-device tree node, see spi/spi-bus.txt
+This switch could have two different management interface.
+
+If SPI interface is used, the device tree node is an SPI device so it must
+reside inside a SPI bus device tree node, see spi/spi-bus.txt
+
+If Platform driver is used, the device tree node is an platform device so it
+must reside inside a platform bus device tree node.
 
 Required properties:
 
@@ -38,6 +43,7 @@ and subnodes of DSA switches.
 
 Examples:
 
+SPI:
 switch@0 {
 	compatible = "vitesse,vsc7395";
 	reg = <0>;
@@ -79,3 +85,46 @@ switch@0 {
 		};
 	};
 };
+
+Platform:
+switch@2,0 {
+	#address-cells = <1>;
+	#size-cells = <1>;
+	compatible = "vitesse,vsc7385";
+	reg = <0x2 0x0 0x20000>;
+	reset-gpios = <&gpio0 12 GPIO_ACTIVE_LOW>;
+
+	ports {
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		port@0 {
+			reg = <0>;
+			label = "lan1";
+		};
+		port@1 {
+			reg = <1>;
+			label = "lan2";
+		};
+		port@2 {
+			reg = <2>;
+			label = "lan3";
+		};
+		port@3 {
+			reg = <3>;
+			label = "lan4";
+		};
+		vsc: port@6 {
+			reg = <6>;
+			label = "cpu";
+			ethernet = <&enet0>;
+			phy-mode = "rgmii";
+			fixed-link {
+				speed = <1000>;
+				full-duplex;
+				pause;
+			};
+		};
+	};
+
+};
-- 
2.20.1

[PATCH v2 2/4] net: dsa: vsc73xx: Split vsc73xx driver

[Pawel Dembicki]

This driver (currently) only takes control of the switch chip over
SPI and configures it to route packages around when connected to a
CPU port. But Vitesse chip support also parallel interface.

This patch split driver into two parts: core and spi. It is required
for add support to another managing interface.

Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Pawel Dembicki <paweldembicki@gmail.com>
---
 drivers/net/dsa/Kconfig                       |  11 +-
 drivers/net/dsa/Makefile                      |   3 +-
 ...tesse-vsc73xx.c => vitesse-vsc73xx-core.c} | 170 +--------------
 drivers/net/dsa/vitesse-vsc73xx-spi.c         | 203 ++++++++++++++++++
 drivers/net/dsa/vitesse-vsc73xx.h             |  29 +++
 5 files changed, 254 insertions(+), 162 deletions(-)
 rename drivers/net/dsa/{vitesse-vsc73xx.c => vitesse-vsc73xx-core.c} (91%)
 create mode 100644 drivers/net/dsa/vitesse-vsc73xx-spi.c
 create mode 100644 drivers/net/dsa/vitesse-vsc73xx.h

diff --git a/drivers/net/dsa/Kconfig b/drivers/net/dsa/Kconfig
index b91e78e3598f..4ab2aa09e2e4 100644
--- a/drivers/net/dsa/Kconfig
+++ b/drivers/net/dsa/Kconfig
@@ -99,8 +99,8 @@ config NET_DSA_SMSC_LAN9303_MDIO
 	  for MDIO managed mode.
 
 config NET_DSA_VITESSE_VSC73XX
-	tristate "Vitesse VSC7385/7388/7395/7398 support"
-	depends on OF && SPI
+	tristate
+	depends on OF
 	depends on NET_DSA
 	select FIXED_PHY
 	select VITESSE_PHY
@@ -109,4 +109,11 @@ config NET_DSA_VITESSE_VSC73XX
 	  This enables support for the Vitesse VSC7385, VSC7388,
 	  VSC7395 and VSC7398 SparX integrated ethernet switches.
 
+config NET_DSA_VITESSE_VSC73XX_SPI
+	tristate "Vitesse VSC7385/7388/7395/7398 SPI mode support"
+	depends on SPI
+	select NET_DSA_VITESSE_VSC73XX
+	---help---
+	  This enables support for the Vitesse VSC7385, VSC7388, VSC7395
+	  and VSC7398 SparX integrated ethernet switches in SPI managed mode.
 endmenu
diff --git a/drivers/net/dsa/Makefile b/drivers/net/dsa/Makefile
index fefb6aaa82ba..117bf78be211 100644
--- a/drivers/net/dsa/Makefile
+++ b/drivers/net/dsa/Makefile
@@ -14,7 +14,8 @@ realtek-objs			:= realtek-smi.o rtl8366.o rtl8366rb.o
 obj-$(CONFIG_NET_DSA_SMSC_LAN9303) += lan9303-core.o
 obj-$(CONFIG_NET_DSA_SMSC_LAN9303_I2C) += lan9303_i2c.o
 obj-$(CONFIG_NET_DSA_SMSC_LAN9303_MDIO) += lan9303_mdio.o
-obj-$(CONFIG_NET_DSA_VITESSE_VSC73XX) += vitesse-vsc73xx.o
+obj-$(CONFIG_NET_DSA_VITESSE_VSC73XX) += vitesse-vsc73xx-core.o
+obj-$(CONFIG_NET_DSA_VITESSE_VSC73XX_SPI) += vitesse-vsc73xx-spi.o
 obj-y				+= b53/
 obj-y				+= microchip/
 obj-y				+= mv88e6xxx/
diff --git a/drivers/net/dsa/vitesse-vsc73xx.c b/drivers/net/dsa/vitesse-vsc73xx-core.c
similarity index 91%
rename from drivers/net/dsa/vitesse-vsc73xx.c
rename to drivers/net/dsa/vitesse-vsc73xx-core.c
index d4780610ea8a..10063f31d9a3 100644
--- a/drivers/net/dsa/vitesse-vsc73xx.c
+++ b/drivers/net/dsa/vitesse-vsc73xx-core.c
@@ -10,10 +10,6 @@
  * handling the switch in a memory-mapped manner by connecting to that external
  * CPU's memory bus.
  *
- * This driver (currently) only takes control of the switch chip over SPI and
- * configures it to route packages around when connected to a CPU port. The
- * chip has embedded PHYs and VLAN support so we model it using DSA.
- *
  * Copyright (C) 2018 Linus Wallej <linus.walleij@linaro.org>
  * Includes portions of code from the firmware uploader by:
  * Copyright (C) 2009 Gabor Juhos <juhosg@openwrt.org>
@@ -24,8 +20,6 @@
 #include <linux/of.h>
 #include <linux/of_device.h>
 #include <linux/of_mdio.h>
-#include <linux/platform_device.h>
-#include <linux/spi/spi.h>
 #include <linux/bitops.h>
 #include <linux/if_bridge.h>
 #include <linux/etherdevice.h>
@@ -34,6 +28,8 @@
 #include <linux/random.h>
 #include <net/dsa.h>
 
+#include "vitesse-vsc73xx.h"
+
 #define VSC73XX_BLOCK_MAC	0x1 /* Subblocks 0-4, 6 (CPU port) */
 #define VSC73XX_BLOCK_ANALYZER	0x2 /* Only subblock 0 */
 #define VSC73XX_BLOCK_MII	0x3 /* Subblocks 0 and 1 */
@@ -255,13 +251,6 @@
 #define VSC73XX_GLORESET_PHY_RESET	BIT(1)
 #define VSC73XX_GLORESET_MASTER_RESET	BIT(0)
 
-#define VSC73XX_CMD_MODE_READ		0
-#define VSC73XX_CMD_MODE_WRITE		1
-#define VSC73XX_CMD_MODE_SHIFT		4
-#define VSC73XX_CMD_BLOCK_SHIFT		5
-#define VSC73XX_CMD_BLOCK_MASK		0x7
-#define VSC73XX_CMD_SUBBLOCK_MASK	0xf
-
 #define VSC7385_CLOCK_DELAY		((3 << 4) | 3)
 #define VSC7385_CLOCK_DELAY_MASK	((3 << 4) | 3)
 
@@ -274,20 +263,6 @@
 				 VSC73XX_ICPU_CTRL_CLK_EN | \
 				 VSC73XX_ICPU_CTRL_SRST)
 
-/**
- * struct vsc73xx - VSC73xx state container
- */
-struct vsc73xx {
-	struct device		*dev;
-	struct gpio_desc	*reset;
-	struct spi_device	*spi;
-	struct dsa_switch	*ds;
-	struct gpio_chip	gc;
-	u16			chipid;
-	u8			addr[ETH_ALEN];
-	struct mutex		lock; /* Protects SPI traffic */
-};
-
 #define IS_7385(a) ((a)->chipid == VSC73XX_CHIPID_ID_7385)
 #define IS_7388(a) ((a)->chipid == VSC73XX_CHIPID_ID_7388)
 #define IS_7395(a) ((a)->chipid == VSC73XX_CHIPID_ID_7395)
@@ -365,7 +340,7 @@ static const struct vsc73xx_counter vsc73xx_tx_counters[] = {
 	{ 29, "TxQoSClass3" }, /* non-standard counter */
 };
 
-static int vsc73xx_is_addr_valid(u8 block, u8 subblock)
+int vsc73xx_is_addr_valid(u8 block, u8 subblock)
 {
 	switch (block) {
 	case VSC73XX_BLOCK_MAC:
@@ -396,96 +371,18 @@ static int vsc73xx_is_addr_valid(u8 block, u8 subblock)
 
 	return 0;
 }
-
-static u8 vsc73xx_make_addr(u8 mode, u8 block, u8 subblock)
-{
-	u8 ret;
-
-	ret = (block & VSC73XX_CMD_BLOCK_MASK) << VSC73XX_CMD_BLOCK_SHIFT;
-	ret |= (mode & 1) << VSC73XX_CMD_MODE_SHIFT;
-	ret |= subblock & VSC73XX_CMD_SUBBLOCK_MASK;
-
-	return ret;
-}
+EXPORT_SYMBOL(vsc73xx_is_addr_valid);
 
 static int vsc73xx_read(struct vsc73xx *vsc, u8 block, u8 subblock, u8 reg,
 			u32 *val)
 {
-	struct spi_transfer t[2];
-	struct spi_message m;
-	u8 cmd[4];
-	u8 buf[4];
-	int ret;
-
-	if (!vsc73xx_is_addr_valid(block, subblock))
-		return -EINVAL;
-
-	spi_message_init(&m);
-
-	memset(&t, 0, sizeof(t));
-
-	t[0].tx_buf = cmd;
-	t[0].len = sizeof(cmd);
-	spi_message_add_tail(&t[0], &m);
-
-	t[1].rx_buf = buf;
-	t[1].len = sizeof(buf);
-	spi_message_add_tail(&t[1], &m);
-
-	cmd[0] = vsc73xx_make_addr(VSC73XX_CMD_MODE_READ, block, subblock);
-	cmd[1] = reg;
-	cmd[2] = 0;
-	cmd[3] = 0;
-
-	mutex_lock(&vsc->lock);
-	ret = spi_sync(vsc->spi, &m);
-	mutex_unlock(&vsc->lock);
-
-	if (ret)
-		return ret;
-
-	*val = (buf[0] << 24) | (buf[1] << 16) | (buf[2] << 8) | buf[3];
-
-	return 0;
+	return vsc->ops->read(vsc, block, subblock, reg, val);
 }
 
 static int vsc73xx_write(struct vsc73xx *vsc, u8 block, u8 subblock, u8 reg,
 			 u32 val)
 {
-	struct spi_transfer t[2];
-	struct spi_message m;
-	u8 cmd[2];
-	u8 buf[4];
-	int ret;
-
-	if (!vsc73xx_is_addr_valid(block, subblock))
-		return -EINVAL;
-
-	spi_message_init(&m);
-
-	memset(&t, 0, sizeof(t));
-
-	t[0].tx_buf = cmd;
-	t[0].len = sizeof(cmd);
-	spi_message_add_tail(&t[0], &m);
-
-	t[1].tx_buf = buf;
-	t[1].len = sizeof(buf);
-	spi_message_add_tail(&t[1], &m);
-
-	cmd[0] = vsc73xx_make_addr(VSC73XX_CMD_MODE_WRITE, block, subblock);
-	cmd[1] = reg;
-
-	buf[0] = (val >> 24) & 0xff;
-	buf[1] = (val >> 16) & 0xff;
-	buf[2] = (val >> 8) & 0xff;
-	buf[3] = val & 0xff;
-
-	mutex_lock(&vsc->lock);
-	ret = spi_sync(vsc->spi, &m);
-	mutex_unlock(&vsc->lock);
-
-	return ret;
+	return vsc->ops->write(vsc, block, subblock, reg, val);
 }
 
 static int vsc73xx_update_bits(struct vsc73xx *vsc, u8 block, u8 subblock,
@@ -1245,21 +1142,11 @@ static int vsc73xx_gpio_probe(struct vsc73xx *vsc)
 	return 0;
 }
 
-static int vsc73xx_probe(struct spi_device *spi)
+int vsc73xx_probe(struct vsc73xx *vsc)
 {
-	struct device *dev = &spi->dev;
-	struct vsc73xx *vsc;
+	struct device *dev = vsc->dev;
 	int ret;
 
-	vsc = devm_kzalloc(dev, sizeof(*vsc), GFP_KERNEL);
-	if (!vsc)
-		return -ENOMEM;
-
-	spi_set_drvdata(spi, vsc);
-	vsc->spi = spi_dev_get(spi);
-	vsc->dev = dev;
-	mutex_init(&vsc->lock);
-
 	/* Release reset, if any */
 	vsc->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
 	if (IS_ERR(vsc->reset)) {
@@ -1270,14 +1157,6 @@ static int vsc73xx_probe(struct spi_device *spi)
 		/* Wait 20ms according to datasheet table 245 */
 		msleep(20);
 
-	spi->mode = SPI_MODE_0;
-	spi->bits_per_word = 8;
-	ret = spi_setup(spi);
-	if (ret < 0) {
-		dev_err(dev, "spi setup failed.\n");
-		return ret;
-	}
-
 	ret = vsc73xx_detect(vsc);
 	if (ret) {
 		dev_err(dev, "no chip found (%d)\n", ret);
@@ -1321,43 +1200,16 @@ static int vsc73xx_probe(struct spi_device *spi)
 
 	return 0;
 }
+EXPORT_SYMBOL(vsc73xx_probe);
 
-static int vsc73xx_remove(struct spi_device *spi)
+int vsc73xx_remove(struct vsc73xx *vsc)
 {
-	struct vsc73xx *vsc = spi_get_drvdata(spi);
-
 	dsa_unregister_switch(vsc->ds);
 	gpiod_set_value(vsc->reset, 1);
 
 	return 0;
 }
-
-static const struct of_device_id vsc73xx_of_match[] = {
-	{
-		.compatible = "vitesse,vsc7385",
-	},
-	{
-		.compatible = "vitesse,vsc7388",
-	},
-	{
-		.compatible = "vitesse,vsc7395",
-	},
-	{
-		.compatible = "vitesse,vsc7398",
-	},
-	{ },
-};
-MODULE_DEVICE_TABLE(of, vsc73xx_of_match);
-
-static struct spi_driver vsc73xx_driver = {
-	.probe = vsc73xx_probe,
-	.remove = vsc73xx_remove,
-	.driver = {
-		.name = "vsc73xx",
-		.of_match_table = vsc73xx_of_match,
-	},
-};
-module_spi_driver(vsc73xx_driver);
+EXPORT_SYMBOL(vsc73xx_remove);
 
 MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
 MODULE_DESCRIPTION("Vitesse VSC7385/7388/7395/7398 driver");
diff --git a/drivers/net/dsa/vitesse-vsc73xx-spi.c b/drivers/net/dsa/vitesse-vsc73xx-spi.c
new file mode 100644
index 000000000000..e73c8fcddc9f
--- /dev/null
+++ b/drivers/net/dsa/vitesse-vsc73xx-spi.c
@@ -0,0 +1,203 @@
+// SPDX-License-Identifier: GPL-2.0
+/* DSA driver for:
+ * Vitesse VSC7385 SparX-G5 5+1-port Integrated Gigabit Ethernet Switch
+ * Vitesse VSC7388 SparX-G8 8-port Integrated Gigabit Ethernet Switch
+ * Vitesse VSC7395 SparX-G5e 5+1-port Integrated Gigabit Ethernet Switch
+ * Vitesse VSC7398 SparX-G8e 8-port Integrated Gigabit Ethernet Switch
+ *
+ * This driver takes control of the switch chip over SPI and
+ * configures it to route packages around when connected to a CPU port.
+ *
+ * Copyright (C) 2018 Linus Wallej <linus.walleij@linaro.org>
+ * Includes portions of code from the firmware uploader by:
+ * Copyright (C) 2009 Gabor Juhos <juhosg@openwrt.org>
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/spi/spi.h>
+
+#include "vitesse-vsc73xx.h"
+
+#define VSC73XX_CMD_SPI_MODE_READ		0
+#define VSC73XX_CMD_SPI_MODE_WRITE		1
+#define VSC73XX_CMD_SPI_MODE_SHIFT		4
+#define VSC73XX_CMD_SPI_BLOCK_SHIFT		5
+#define VSC73XX_CMD_SPI_BLOCK_MASK		0x7
+#define VSC73XX_CMD_SPI_SUBBLOCK_MASK		0xf
+
+/**
+ * struct vsc73xx_spi - VSC73xx SPI state container
+ */
+struct vsc73xx_spi {
+	struct spi_device	*spi;
+	struct mutex		lock; /* Protects SPI traffic */
+	struct vsc73xx		vsc;
+};
+
+static const struct vsc73xx_ops vsc73xx_spi_ops;
+
+static u8 vsc73xx_make_addr(u8 mode, u8 block, u8 subblock)
+{
+	u8 ret;
+
+	ret =
+	    (block & VSC73XX_CMD_SPI_BLOCK_MASK) << VSC73XX_CMD_SPI_BLOCK_SHIFT;
+	ret |= (mode & 1) << VSC73XX_CMD_SPI_MODE_SHIFT;
+	ret |= subblock & VSC73XX_CMD_SPI_SUBBLOCK_MASK;
+
+	return ret;
+}
+
+static int vsc73xx_spi_read(struct vsc73xx *vsc, u8 block, u8 subblock, u8 reg,
+			    u32 *val)
+{
+	struct vsc73xx_spi *vsc_spi = vsc->priv;
+	struct spi_transfer t[2];
+	struct spi_message m;
+	u8 cmd[4];
+	u8 buf[4];
+	int ret;
+
+	if (!vsc73xx_is_addr_valid(block, subblock))
+		return -EINVAL;
+
+	spi_message_init(&m);
+
+	memset(&t, 0, sizeof(t));
+
+	t[0].tx_buf = cmd;
+	t[0].len = sizeof(cmd);
+	spi_message_add_tail(&t[0], &m);
+
+	t[1].rx_buf = buf;
+	t[1].len = sizeof(buf);
+	spi_message_add_tail(&t[1], &m);
+
+	cmd[0] = vsc73xx_make_addr(VSC73XX_CMD_SPI_MODE_READ, block, subblock);
+	cmd[1] = reg;
+	cmd[2] = 0;
+	cmd[3] = 0;
+
+	mutex_lock(&vsc_spi->lock);
+	ret = spi_sync(vsc_spi->spi, &m);
+	mutex_unlock(&vsc_spi->lock);
+
+	if (ret)
+		return ret;
+
+	*val = (buf[0] << 24) | (buf[1] << 16) | (buf[2] << 8) | buf[3];
+
+	return 0;
+}
+
+static int vsc73xx_spi_write(struct vsc73xx *vsc, u8 block, u8 subblock, u8 reg,
+			     u32 val)
+{
+	struct vsc73xx_spi *vsc_spi = vsc->priv;
+	struct spi_transfer t[2];
+	struct spi_message m;
+	u8 cmd[2];
+	u8 buf[4];
+	int ret;
+
+	if (!vsc73xx_is_addr_valid(block, subblock))
+		return -EINVAL;
+
+	spi_message_init(&m);
+
+	memset(&t, 0, sizeof(t));
+
+	t[0].tx_buf = cmd;
+	t[0].len = sizeof(cmd);
+	spi_message_add_tail(&t[0], &m);
+
+	t[1].tx_buf = buf;
+	t[1].len = sizeof(buf);
+	spi_message_add_tail(&t[1], &m);
+
+	cmd[0] = vsc73xx_make_addr(VSC73XX_CMD_SPI_MODE_WRITE, block, subblock);
+	cmd[1] = reg;
+
+	buf[0] = (val >> 24) & 0xff;
+	buf[1] = (val >> 16) & 0xff;
+	buf[2] = (val >> 8) & 0xff;
+	buf[3] = val & 0xff;
+
+	mutex_lock(&vsc_spi->lock);
+	ret = spi_sync(vsc_spi->spi, &m);
+	mutex_unlock(&vsc_spi->lock);
+
+	return ret;
+}
+
+static int vsc73xx_spi_probe(struct spi_device *spi)
+{
+	struct device *dev = &spi->dev;
+	struct vsc73xx_spi *vsc_spi;
+	int ret;
+
+	vsc_spi = devm_kzalloc(dev, sizeof(*vsc_spi), GFP_KERNEL);
+	if (!vsc_spi)
+		return -ENOMEM;
+
+	spi_set_drvdata(spi, vsc_spi);
+	vsc_spi->spi = spi_dev_get(spi);
+	vsc_spi->vsc.dev = dev;
+	vsc_spi->vsc.priv = vsc_spi;
+	vsc_spi->vsc.ops = &vsc73xx_spi_ops;
+	mutex_init(&vsc_spi->lock);
+
+	spi->mode = SPI_MODE_0;
+	spi->bits_per_word = 8;
+	ret = spi_setup(spi);
+	if (ret < 0) {
+		dev_err(dev, "spi setup failed.\n");
+		return ret;
+	}
+
+	return vsc73xx_probe(&vsc_spi->vsc);
+}
+
+static int vsc73xx_spi_remove(struct spi_device *spi)
+{
+	struct vsc73xx_spi *vsc_spi = spi_get_drvdata(spi);
+
+	return vsc73xx_remove(&vsc_spi->vsc);
+}
+
+static const struct vsc73xx_ops vsc73xx_spi_ops = {
+	.read = vsc73xx_spi_read,
+	.write = vsc73xx_spi_write,
+};
+
+static const struct of_device_id vsc73xx_of_match[] = {
+	{
+		.compatible = "vitesse,vsc7385",
+	},
+	{
+		.compatible = "vitesse,vsc7388",
+	},
+	{
+		.compatible = "vitesse,vsc7395",
+	},
+	{
+		.compatible = "vitesse,vsc7398",
+	},
+	{ },
+};
+MODULE_DEVICE_TABLE(of, vsc73xx_of_match);
+
+static struct spi_driver vsc73xx_spi_driver = {
+	.probe = vsc73xx_spi_probe,
+	.remove = vsc73xx_spi_remove,
+	.driver = {
+		.name = "vsc73xx-spi",
+		.of_match_table = vsc73xx_of_match,
+	},
+};
+module_spi_driver(vsc73xx_spi_driver);
+
+MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
+MODULE_DESCRIPTION("Vitesse VSC7385/7388/7395/7398 SPI driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/net/dsa/vitesse-vsc73xx.h b/drivers/net/dsa/vitesse-vsc73xx.h
new file mode 100644
index 000000000000..7478f8d4e0a9
--- /dev/null
+++ b/drivers/net/dsa/vitesse-vsc73xx.h
@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <linux/device.h>
+#include <linux/etherdevice.h>
+#include <linux/gpio/driver.h>
+
+/**
+ * struct vsc73xx - VSC73xx state container
+ */
+struct vsc73xx {
+	struct device			*dev;
+	struct gpio_desc		*reset;
+	struct dsa_switch		*ds;
+	struct gpio_chip		gc;
+	u16				chipid;
+	u8				addr[ETH_ALEN];
+	const struct vsc73xx_ops	*ops;
+	void				*priv;
+};
+
+struct vsc73xx_ops {
+	int (*read)(struct vsc73xx *vsc, u8 block, u8 subblock, u8 reg,
+		    u32 *val);
+	int (*write)(struct vsc73xx *vsc, u8 block, u8 subblock, u8 reg,
+		     u32 val);
+};
+
+int vsc73xx_is_addr_valid(u8 block, u8 subblock);
+int vsc73xx_probe(struct vsc73xx *vsc);
+int vsc73xx_remove(struct vsc73xx *vsc);
-- 
2.20.1

[PATCH v2 3/4] net: dsa: vsc73xx: add support for parallel mode

[Pawel Dembicki]

This patch add platform part of vsc73xx driver.
It allows to use chip connected by parallel interface.

Signed-off-by: Pawel Dembicki <paweldembicki@gmail.com>
---
 drivers/net/dsa/Kconfig                    |   8 ++
 drivers/net/dsa/Makefile                   |   1 +
 drivers/net/dsa/vitesse-vsc73xx-platform.c | 160 +++++++++++++++++++++
 3 files changed, 169 insertions(+)
 create mode 100644 drivers/net/dsa/vitesse-vsc73xx-platform.c

diff --git a/drivers/net/dsa/Kconfig b/drivers/net/dsa/Kconfig
index 4ab2aa09e2e4..80965808949d 100644
--- a/drivers/net/dsa/Kconfig
+++ b/drivers/net/dsa/Kconfig
@@ -116,4 +116,12 @@ config NET_DSA_VITESSE_VSC73XX_SPI
 	---help---
 	  This enables support for the Vitesse VSC7385, VSC7388, VSC7395
 	  and VSC7398 SparX integrated ethernet switches in SPI managed mode.
+
+config NET_DSA_VITESSE_VSC73XX_PLATFORM
+	tristate "Vitesse VSC7385/7388/7395/7398 Platform mode support"
+	depends on HAS_IOMEM
+	select NET_DSA_VITESSE_VSC73XX
+	---help---
+	  This enables support for the Vitesse VSC7385, VSC7388, VSC7395
+	  and VSC7398 SparX integrated ethernet switches in Platform managed mode.
 endmenu
diff --git a/drivers/net/dsa/Makefile b/drivers/net/dsa/Makefile
index 117bf78be211..d5e4c668ac03 100644
--- a/drivers/net/dsa/Makefile
+++ b/drivers/net/dsa/Makefile
@@ -15,6 +15,7 @@ obj-$(CONFIG_NET_DSA_SMSC_LAN9303) += lan9303-core.o
 obj-$(CONFIG_NET_DSA_SMSC_LAN9303_I2C) += lan9303_i2c.o
 obj-$(CONFIG_NET_DSA_SMSC_LAN9303_MDIO) += lan9303_mdio.o
 obj-$(CONFIG_NET_DSA_VITESSE_VSC73XX) += vitesse-vsc73xx-core.o
+obj-$(CONFIG_NET_DSA_VITESSE_VSC73XX_PLATFORM) += vitesse-vsc73xx-platform.o
 obj-$(CONFIG_NET_DSA_VITESSE_VSC73XX_SPI) += vitesse-vsc73xx-spi.o
 obj-y				+= b53/
 obj-y				+= microchip/
diff --git a/drivers/net/dsa/vitesse-vsc73xx-platform.c b/drivers/net/dsa/vitesse-vsc73xx-platform.c
new file mode 100644
index 000000000000..f41dbacd0b19
--- /dev/null
+++ b/drivers/net/dsa/vitesse-vsc73xx-platform.c
@@ -0,0 +1,160 @@
+// SPDX-License-Identifier: GPL-2.0
+/* DSA driver for:
+ * Vitesse VSC7385 SparX-G5 5+1-port Integrated Gigabit Ethernet Switch
+ * Vitesse VSC7388 SparX-G8 8-port Integrated Gigabit Ethernet Switch
+ * Vitesse VSC7395 SparX-G5e 5+1-port Integrated Gigabit Ethernet Switch
+ * Vitesse VSC7398 SparX-G8e 8-port Integrated Gigabit Ethernet Switch
+ *
+ * This driver takes control of the switch chip over Platform and
+ * configures it to route packages around when connected to a CPU port.
+ *
+ * Copyright (C) 2019 pawel Dembicki <paweldembicki@gmail.com>
+ * Based on vitesse-vsc-spi.c by:
+ * Copyright (C) 2018 Linus Wallej <linus.walleij@linaro.org>
+ * Includes portions of code from the firmware uploader by:
+ * Copyright (C) 2009 Gabor Juhos <juhosg@openwrt.org>
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+
+#include "vitesse-vsc73xx.h"
+
+#define VSC73XX_CMD_PLATFORM_BLOCK_SHIFT		14
+#define VSC73XX_CMD_PLATFORM_BLOCK_MASK			0x7
+#define VSC73XX_CMD_PLATFORM_SUBBLOCK_SHIFT		10
+#define VSC73XX_CMD_PLATFORM_SUBBLOCK_MASK		0xf
+#define VSC73XX_CMD_PLATFORM_REGISTER_SHIFT		2
+
+/**
+ * struct vsc73xx_platform - VSC73xx Platform state container
+ */
+struct vsc73xx_platform {
+	struct platform_device	*pdev;
+	void __iomem		*base_addr;
+	struct vsc73xx		vsc;
+};
+
+static const struct vsc73xx_ops vsc73xx_platform_ops;
+
+static u32 vsc73xx_make_addr(u8 block, u8 subblock, u8 reg)
+{
+	u32 ret;
+
+	ret = (block & VSC73XX_CMD_PLATFORM_BLOCK_MASK)
+	    << VSC73XX_CMD_PLATFORM_BLOCK_SHIFT;
+	ret |= (subblock & VSC73XX_CMD_PLATFORM_SUBBLOCK_MASK)
+	    << VSC73XX_CMD_PLATFORM_SUBBLOCK_SHIFT;
+	ret |= reg << VSC73XX_CMD_PLATFORM_REGISTER_SHIFT;
+
+	return ret;
+}
+
+static int vsc73xx_platform_read(struct vsc73xx *vsc, u8 block, u8 subblock,
+				 u8 reg, u32 *val)
+{
+	struct vsc73xx_platform *vsc_platform = vsc->priv;
+	u32 offset;
+
+	if (!vsc73xx_is_addr_valid(block, subblock))
+		return -EINVAL;
+
+	offset = vsc73xx_make_addr(block, subblock, reg);
+	*val = ioread32be(vsc_platform->base_addr + offset);
+
+	return 0;
+}
+
+static int vsc73xx_platform_write(struct vsc73xx *vsc, u8 block, u8 subblock,
+				  u8 reg, u32 val)
+{
+	struct vsc73xx_platform *vsc_platform = vsc->priv;
+	u32 offset;
+
+	if (!vsc73xx_is_addr_valid(block, subblock))
+		return -EINVAL;
+
+	offset = vsc73xx_make_addr(block, subblock, reg);
+	iowrite32be(val, vsc_platform->base_addr + offset);
+
+	return 0;
+}
+
+static int vsc73xx_platform_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct vsc73xx_platform *vsc_platform;
+	struct resource *res = NULL;
+	int ret;
+
+	vsc_platform = devm_kzalloc(dev, sizeof(*vsc_platform), GFP_KERNEL);
+	if (!vsc_platform)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, vsc_platform);
+	vsc_platform->pdev = pdev;
+	vsc_platform->vsc.dev = dev;
+	vsc_platform->vsc.priv = vsc_platform;
+	vsc_platform->vsc.ops = &vsc73xx_platform_ops;
+
+	/* obtain I/O memory space */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "cannot obtain I/O memory space\n");
+		ret = -ENXIO;
+		return ret;
+	}
+
+	vsc_platform->base_addr = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(vsc_platform->base_addr)) {
+		dev_err(&pdev->dev, "cannot request I/O memory space\n");
+		ret = -ENXIO;
+		return ret;
+	}
+
+	return vsc73xx_probe(&vsc_platform->vsc);
+}
+
+static int vsc73xx_platform_remove(struct platform_device *pdev)
+{
+	struct vsc73xx_platform *vsc_platform = platform_get_drvdata(pdev);
+
+	return vsc73xx_remove(&vsc_platform->vsc);
+}
+
+static const struct vsc73xx_ops vsc73xx_platform_ops = {
+	.read = vsc73xx_platform_read,
+	.write = vsc73xx_platform_write,
+};
+
+static const struct of_device_id vsc73xx_of_match[] = {
+	{
+		.compatible = "vitesse,vsc7385",
+	},
+	{
+		.compatible = "vitesse,vsc7388",
+	},
+	{
+		.compatible = "vitesse,vsc7395",
+	},
+	{
+		.compatible = "vitesse,vsc7398",
+	},
+	{ },
+};
+MODULE_DEVICE_TABLE(of, vsc73xx_of_match);
+
+static struct platform_driver vsc73xx_platform_driver = {
+	.probe = vsc73xx_platform_probe,
+	.remove = vsc73xx_platform_remove,
+	.driver = {
+		.name = "vsc73xx-platform",
+		.of_match_table = vsc73xx_of_match,
+	},
+};
+module_platform_driver(vsc73xx_platform_driver);
+
+MODULE_AUTHOR("Pawel Dembicki <paweldembicki@gmail.com>");
+MODULE_DESCRIPTION("Vitesse VSC7385/7388/7395/7398 Platform driver");
+MODULE_LICENSE("GPL v2");
-- 
2.20.1

[PATCH v2 4/4] net: dsa: vsc73xx: Assert reset if iCPU is enabled

[Pawel Dembicki]

Driver allow to use devices with disabled iCPU only.

Some devices have pre-initialised iCPU by bootloader.
That state make switch unmanaged. This patch force reset
if device is in unmanaged state. In the result chip lost
internal firmware from RAM and it can be managed.

Signed-off-by: Pawel Dembicki <paweldembicki@gmail.com>
---
 drivers/net/dsa/vitesse-vsc73xx-core.c | 36 ++++++++++++--------------
 1 file changed, 17 insertions(+), 19 deletions(-)

diff --git a/drivers/net/dsa/vitesse-vsc73xx-core.c b/drivers/net/dsa/vitesse-vsc73xx-core.c
index 10063f31d9a3..4525702faf68 100644
--- a/drivers/net/dsa/vitesse-vsc73xx-core.c
+++ b/drivers/net/dsa/vitesse-vsc73xx-core.c
@@ -417,22 +417,8 @@ static int vsc73xx_detect(struct vsc73xx *vsc)
 	}
 
 	if (val == 0xffffffff) {
-		dev_info(vsc->dev, "chip seems dead, assert reset\n");
-		gpiod_set_value_cansleep(vsc->reset, 1);
-		/* Reset pulse should be 20ns minimum, according to datasheet
-		 * table 245, so 10us should be fine
-		 */
-		usleep_range(10, 100);
-		gpiod_set_value_cansleep(vsc->reset, 0);
-		/* Wait 20ms according to datasheet table 245 */
-		msleep(20);
-
-		ret = vsc73xx_read(vsc, VSC73XX_BLOCK_SYSTEM, 0,
-				   VSC73XX_ICPU_MBOX_VAL, &val);
-		if (val == 0xffffffff) {
-			dev_err(vsc->dev, "seems not to help, giving up\n");
-			return -ENODEV;
-		}
+		dev_info(vsc->dev, "chip seems dead.\n");
+		return -EAGAIN;
 	}
 
 	ret = vsc73xx_read(vsc, VSC73XX_BLOCK_SYSTEM, 0,
@@ -483,9 +469,8 @@ static int vsc73xx_detect(struct vsc73xx *vsc)
 	}
 	if (icpu_si_boot_en && !icpu_pi_en) {
 		dev_err(vsc->dev,
-			"iCPU enabled boots from SI, no external memory\n");
-		dev_err(vsc->dev, "no idea how to deal with this\n");
-		return -ENODEV;
+			"iCPU enabled boots from PI/SI, no external memory\n");
+		return -EAGAIN;
 	}
 	if (!icpu_si_boot_en && icpu_pi_en) {
 		dev_err(vsc->dev,
@@ -1158,6 +1143,19 @@ int vsc73xx_probe(struct vsc73xx *vsc)
 		msleep(20);
 
 	ret = vsc73xx_detect(vsc);
+	if (ret == -EAGAIN) {
+		dev_err(vsc->dev,
+			"Chip seams to be out of control. Assert reset and try again.\n");
+		gpiod_set_value_cansleep(vsc->reset, 1);
+		/* Reset pulse should be 20ns minimum, according to datasheet
+		 * table 245, so 10us should be fine
+		 */
+		usleep_range(10, 100);
+		gpiod_set_value_cansleep(vsc->reset, 0);
+		/* Wait 20ms according to datasheet table 245 */
+		msleep(20);
+		ret = vsc73xx_detect(vsc);
+	}
 	if (ret) {
 		dev_err(dev, "no chip found (%d)\n", ret);
 		return -ENODEV;
-- 
2.20.1

Re: [PATCH v2 1/4] net: dsa: Change DT bindings for Vitesse VSC73xx switches

[Linus Walleij]

On Wed, Jul 3, 2019 at 7:21 PM Pawel Dembicki <paweldembicki@gmail.com> wrote:

> This commit introduce how to use vsc73xx platform driver.
>
> Signed-off-by: Pawel Dembicki <paweldembicki@gmail.com>

Nice!

> +If Platform driver is used, the device tree node is an platform device so it
> +must reside inside a platform bus device tree node.

I would write something like "when connected to a memory bus, and
used in memory-mapped I/O mode, a platform device is used to represent
the vsc73xx" so it is clear what is going on.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Yours,
Linus Walleij

Re: [PATCH v2 2/4] net: dsa: vsc73xx: Split vsc73xx driver

[Linus Walleij]

On Wed, Jul 3, 2019 at 7:21 PM Pawel Dembicki <paweldembicki@gmail.com> wrote:

> This driver (currently) only takes control of the switch chip over
> SPI and configures it to route packages around when connected to a
> CPU port. But Vitesse chip support also parallel interface.
>
> This patch split driver into two parts: core and spi. It is required
> for add support to another managing interface.
>
> Tested-by: Linus Walleij <linus.walleij@linaro.org>
> Signed-off-by: Pawel Dembicki <paweldembicki@gmail.com>

That's a nice and clean split.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Yours,
Linus Walleij

Re: [PATCH v2 3/4] net: dsa: vsc73xx: add support for parallel mode

[Linus Walleij]

Hi Pawel,

this looks overall good and the following is just
documentation nit-pick so feel free to add my
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

On Wed, Jul 3, 2019 at 7:21 PM Pawel Dembicki <paweldembicki@gmail.com> wrote:

> This patch add platform part of vsc73xx driver.
> It allows to use chip connected by parallel interface.
>
> Signed-off-by: Pawel Dembicki <paweldembicki@gmail.com>

I would elaborate on the fact that we're dealing with memory-mapped
I/O but perhaps even more important to do that in the source code file and
Kconfig so it is close to the users rather than in the changelog.

Write something about the address bus wireing making all
accesses big endian.

> +config NET_DSA_VITESSE_VSC73XX_PLATFORM
> +       tristate "Vitesse VSC7385/7388/7395/7398 Platform mode support"
> +       depends on HAS_IOMEM
> +       select NET_DSA_VITESSE_VSC73XX
> +       ---help---
> +         This enables support for the Vitesse VSC7385, VSC7388, VSC7395
> +         and VSC7398 SparX integrated ethernet switches in Platform managed mode.

I would insert something about memory-mapped I/O mode
over a CPU-attached address bus.

Yours,
Linus Walleij

Re: [PATCH v2 4/4] net: dsa: vsc73xx: Assert reset if iCPU is enabled

[Linus Walleij]

On Wed, Jul 3, 2019 at 7:21 PM Pawel Dembicki <paweldembicki@gmail.com> wrote:

> Driver allow to use devices with disabled iCPU only.
>
> Some devices have pre-initialised iCPU by bootloader.
> That state make switch unmanaged. This patch force reset
> if device is in unmanaged state. In the result chip lost
> internal firmware from RAM and it can be managed.
>
> Signed-off-by: Pawel Dembicki <paweldembicki@gmail.com>

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

My devices do not have direct access to the reset line so I
can't assert reset no matter how I try, if it works for you, the
code is certainly better like this.

Yours,
Linus Walleij

Re: [PATCH v2 0/4] net: dsa: Add Vitesse VSC73xx parallel mode

[David Miller]

From: Pawel Dembicki <paweldembicki@gmail.com>
Date: Wed,  3 Jul 2019 19:19:20 +0200

> Main goal of this patch series is to add support for parallel bus in
> Vitesse VSC73xx switches. Existing driver supports only SPI mode.
> 
> Second change is needed for devices in unmanaged state.

Please respin with the documentation description changes suggested
in the review for this series.

Thanks.

Re: [PATCH v2 1/4] net: dsa: Change DT bindings for Vitesse VSC73xx switches

[Florian Fainelli]

On 7/4/2019 12:05 AM, Linus Walleij wrote:
> On Wed, Jul 3, 2019 at 7:21 PM Pawel Dembicki <paweldembicki@gmail.com> wrote:
> 
>> This commit introduce how to use vsc73xx platform driver.
>>
>> Signed-off-by: Pawel Dembicki <paweldembicki@gmail.com>
> 
> Nice!
> 
>> +If Platform driver is used, the device tree node is an platform device so it
>> +must reside inside a platform bus device tree node.
> 
> I would write something like "when connected to a memory bus, and
> used in memory-mapped I/O mode, a platform device is used to represent
> the vsc73xx" so it is clear what is going on.

Agreed, with that fixed:

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian

Re: [PATCH v2 2/4] net: dsa: vsc73xx: Split vsc73xx driver

[Florian Fainelli]

On 7/3/2019 10:19 AM, Pawel Dembicki wrote:
> This driver (currently) only takes control of the switch chip over
> SPI and configures it to route packages around when connected to a
> CPU port. But Vitesse chip support also parallel interface.
> 
> This patch split driver into two parts: core and spi. It is required
> for add support to another managing interface.
> 
> Tested-by: Linus Walleij <linus.walleij@linaro.org>
> Signed-off-by: Pawel Dembicki <paweldembicki@gmail.com>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian

Re: [PATCH v2 4/4] net: dsa: vsc73xx: Assert reset if iCPU is enabled

[Florian Fainelli]

On 7/3/2019 10:19 AM, Pawel Dembicki wrote:
> Driver allow to use devices with disabled iCPU only.
> 
> Some devices have pre-initialised iCPU by bootloader.
> That state make switch unmanaged. This patch force reset
> if device is in unmanaged state. In the result chip lost
> internal firmware from RAM and it can be managed.
> 
> Signed-off-by: Pawel Dembicki <paweldembicki@gmail.com>
> ---

[snip]

> @@ -1158,6 +1143,19 @@ int vsc73xx_probe(struct vsc73xx *vsc)
>  		msleep(20);
>  
>  	ret = vsc73xx_detect(vsc);
> +	if (ret == -EAGAIN) {
> +		dev_err(vsc->dev,
> +			"Chip seams to be out of control. Assert reset and try again.\n");
> +		gpiod_set_value_cansleep(vsc->reset, 1);

s/seams/seems/

With that fixed:

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian

Re: [PATCH v2 4/4] net: dsa: vsc73xx: Assert reset if iCPU is enabled

[Paweł Dembicki]

On 4/7/19 09:22 Linus Walleij <linus.walleij@linaro.org> wrote:
>
> My devices do not have direct access to the reset line so I
> can't assert reset no matter how I try, if it works for you, the
> code is certainly better like this.
>

In P2020RDB, VSC7385 reset is connected to GPIO. U-boot put binary
file to iCPU and make VSC7385 unmanaged.
However reset flush internal memory and iCPU stop.
In this case bootlog looks like that:

[    2.989047] vsc73xx-platform ffb00000.switch: VSC7385 (rev: 2) switch found
[    2.996192] vsc73xx-platform ffb00000.switch: iCPU enabled boots
from PI/SI, no external memory
[    3.005057] vsc73xx-platform ffb00000.switch: Chip seems to be out
of control. Assert reset and try again.
[    3.045034] vsc73xx-platform ffb00000.switch: VSC7385 (rev: 2) switch found
[    3.052171] vsc73xx-platform ffb00000.switch: iCPU disabled, no
external memory

Best Regards,
Pawel Dembicki

[PATCH v2 4/4] net: dsa: vsc73xx: Assert reset if iCPU is enabled

[Pawel Dembicki]

Driver allow to use devices with disabled iCPU only.

Some devices have pre-initialised iCPU by bootloader.
That state make switch unmanaged. This patch force reset
if device is in unmanaged state. In the result chip lost
internal firmware from RAM and it can be managed.

Signed-off-by: Pawel Dembicki <paweldembicki@gmail.com>
---
Changes in v2:
- rebase commit after changes 1-3/4 patches

 drivers/net/dsa/vitesse-vsc73xx-core.c | 36 ++++++++++++--------------
 1 file changed, 17 insertions(+), 19 deletions(-)

diff --git a/drivers/net/dsa/vitesse-vsc73xx-core.c b/drivers/net/dsa/vitesse-vsc73xx-core.c
index 10063f31d9a3..4525702faf68 100644
--- a/drivers/net/dsa/vitesse-vsc73xx-core.c
+++ b/drivers/net/dsa/vitesse-vsc73xx-core.c
@@ -417,22 +417,8 @@ static int vsc73xx_detect(struct vsc73xx *vsc)
 	}
 
 	if (val == 0xffffffff) {
-		dev_info(vsc->dev, "chip seems dead, assert reset\n");
-		gpiod_set_value_cansleep(vsc->reset, 1);
-		/* Reset pulse should be 20ns minimum, according to datasheet
-		 * table 245, so 10us should be fine
-		 */
-		usleep_range(10, 100);
-		gpiod_set_value_cansleep(vsc->reset, 0);
-		/* Wait 20ms according to datasheet table 245 */
-		msleep(20);
-
-		ret = vsc73xx_read(vsc, VSC73XX_BLOCK_SYSTEM, 0,
-				   VSC73XX_ICPU_MBOX_VAL, &val);
-		if (val == 0xffffffff) {
-			dev_err(vsc->dev, "seems not to help, giving up\n");
-			return -ENODEV;
-		}
+		dev_info(vsc->dev, "chip seems dead.\n");
+		return -EAGAIN;
 	}
 
 	ret = vsc73xx_read(vsc, VSC73XX_BLOCK_SYSTEM, 0,
@@ -483,9 +469,8 @@ static int vsc73xx_detect(struct vsc73xx *vsc)
 	}
 	if (icpu_si_boot_en && !icpu_pi_en) {
 		dev_err(vsc->dev,
-			"iCPU enabled boots from SI, no external memory\n");
-		dev_err(vsc->dev, "no idea how to deal with this\n");
-		return -ENODEV;
+			"iCPU enabled boots from PI/SI, no external memory\n");
+		return -EAGAIN;
 	}
 	if (!icpu_si_boot_en && icpu_pi_en) {
 		dev_err(vsc->dev,
@@ -1158,6 +1143,19 @@ int vsc73xx_probe(struct vsc73xx *vsc)
 		msleep(20);
 
 	ret = vsc73xx_detect(vsc);
+	if (ret == -EAGAIN) {
+		dev_err(vsc->dev,
+			"Chip seams to be out of control. Assert reset and try again.\n");
+		gpiod_set_value_cansleep(vsc->reset, 1);
+		/* Reset pulse should be 20ns minimum, according to datasheet
+		 * table 245, so 10us should be fine
+		 */
+		usleep_range(10, 100);
+		gpiod_set_value_cansleep(vsc->reset, 0);
+		/* Wait 20ms according to datasheet table 245 */
+		msleep(20);
+		ret = vsc73xx_detect(vsc);
+	}
 	if (ret) {
 		dev_err(dev, "no chip found (%d)\n", ret);
 		return -ENODEV;
-- 
2.20.1