[PATCH net-next 1/2] net: mdio-mux-mmioreg: Add support for 16bit and 32bit register sizes

Neil Armstrong
2016-11-04T15:51:31Z

In order to support PHY switching on Amlogic GXL SoCs, add support for
16bit and 32bit registers sizes.

Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
---
.../devicetree/bindings/net/mdio-mux-mmioreg.txt | 4 +-
drivers/net/phy/mdio-mux-mmioreg.c | 60 +++++++++++++++++-----
2 files changed, 49 insertions(+), 15 deletions(-)

diff --git a/Documentation/devicetree/bindings/net/mdio-mux-mmioreg.txt b/Documentation/devicetree/bindings/net/mdio-mux-mmioreg.txt
index 8516929..065e8bd 100644
--- a/Documentation/devicetree/bindings/net/mdio-mux-mmioreg.txt
+++ b/Documentation/devicetree/bindings/net/mdio-mux-mmioreg.txt
@@ -3,7 +3,7 @@ Properties for an MDIO bus multiplexer controlled by a memory-mapped device
This is a special case of a MDIO bus multiplexer. A memory-mapped device,
like an FPGA, is used to control which child bus is connected. The mdio-mux
node must be a child of the memory-mapped device. The driver currently only
-supports devices with eight-bit registers.
+supports devices with 8, 16 or 32-bit registers.

Required properties in addition to the generic multiplexer properties:

@@ -11,7 +11,7 @@ Required properties in addition to the generic multiplexer properties:

- reg : integer, contains the offset of the register that controls the bus
multiplexer. The size field in the 'reg' property is the size of
- register, and must therefore be 1.
+ register, and must therefore be 1, 2, or 4.

- mux-mask : integer, contains an eight-bit mask that specifies which
bits in the register control the actual bus multiplexer. The
diff --git a/drivers/net/phy/mdio-mux-mmioreg.c b/drivers/net/phy/mdio-mux-mmioreg.c
index d0bed52..6a33646 100644
--- a/drivers/net/phy/mdio-mux-mmioreg.c
+++ b/drivers/net/phy/mdio-mux-mmioreg.c
@@ -21,7 +21,8 @@
struct mdio_mux_mmioreg_state {
void *mux_handle;
phys_addr_t phys;
- uint8_t mask;
+ unsigned int iosize;
+ unsigned int mask;
};

/*
@@ -47,17 +48,47 @@ static int mdio_mux_mmioreg_switch_fn(int current_child, int desired_child,
struct mdio_mux_mmioreg_state *s = data;

if (current_child ^ desired_child) {
- void __iomem *p = ioremap(s->phys, 1);
- uint8_t x, y;
-
+ void __iomem *p = ioremap(s->phys, s->iosize);
if (!p)
return -ENOMEM;

- x = ioread8(p);
- y = (x & ~s->mask) | desired_child;
- if (x != y) {
- iowrite8((x & ~s->mask) | desired_child, p);
- pr_debug("%s: %02x -> %02x\n", __func__, x, y);
+ switch (s->iosize) {
+ case sizeof(uint8_t): {
+ uint8_t x, y;
+
+ x = ioread8(p);
+ y = (x & ~s->mask) | desired_child;
+ if (x != y) {
+ iowrite8((x & ~s->mask) | desired_child, p);
+ pr_debug("%s: %02x -> %02x\n", __func__, x, y);
+ }
+
+ break;
+ }
+ case sizeof(uint16_t): {
+ uint16_t x, y;
+
+ x = ioread16(p);
+ y = (x & ~s->mask) | desired_child;
+ if (x != y) {
+ iowrite16((x & ~s->mask) | desired_child, p);
+ pr_debug("%s: %04x -> %04x\n", __func__, x, y);
+ }
+
+ break;
+ }
+ case sizeof(uint32_t): {
+ uint32_t x, y;
+
+ x = ioread32(p);
+ y = (x & ~s->mask) | desired_child;
+ if (x != y) {
+ iowrite32((x & ~s->mask) | desired_child, p);
+ pr_debug("%s: %08x -> %08x\n", __func__, x, y);
+ }
+
+ break;
+ }
}

iounmap(p);
@@ -88,8 +119,11 @@ static int mdio_mux_mmioreg_probe(struct platform_device *pdev)
}
s->phys = res.start;

- if (resource_size(&res) != sizeof(uint8_t)) {
- dev_err(&pdev->dev, "only 8-bit registers are supported\n");
+ s->iosize = resource_size(&res);
+ if (s->iosize != sizeof(uint8_t) &&
+ s->iosize != sizeof(uint16_t) &&
+ s->iosize != sizeof(uint32_t)) {
+ dev_err(&pdev->dev, "only 8/16/32-bit registers are supported\n");
return -EINVAL;
}

@@ -98,8 +132,8 @@ static int mdio_mux_mmioreg_probe(struct platform_device *pdev)
dev_err(&pdev->dev, "missing or invalid mux-mask property\n");
return -ENODEV;
}
- if (be32_to_cpup(iprop) > 255) {
- dev_err(&pdev->dev, "only 8-bit registers are supported\n");
+ if (be32_to_cpup(iprop) >= BIT(s->iosize * 8)) {
+ dev_err(&pdev->dev, "only 8/16/32-bit registers are supported\n");
return -EINVAL;
}
s->mask = be32_to_cpup(iprop);
--
1.9.1