diff options
author | Rasmus Villemoes <linux@rasmusvillemoes.dk> | 2022-06-14 10:46:12 +0200 |
---|---|---|
committer | Jakub Kicinski <kuba@kernel.org> | 2022-06-16 20:29:06 -0700 |
commit | 5c2d0a6a0701ba86a4bb0bf1876266c751e328bd (patch) | |
tree | a3191c55afbe8ec7ad8714ce8179dd44992c762e /drivers/net/phy/dp83867.c | |
parent | a793679827a87b01f9d973ea30b923cd5a3ff2c5 (diff) | |
download | linux-stable-5c2d0a6a0701ba86a4bb0bf1876266c751e328bd.tar.gz linux-stable-5c2d0a6a0701ba86a4bb0bf1876266c751e328bd.tar.bz2 linux-stable-5c2d0a6a0701ba86a4bb0bf1876266c751e328bd.zip |
net: phy: dp83867: implement support for io_impedance_ctrl nvmem cell
We have a board where measurements indicate that the current three
options - leaving IO_IMPEDANCE_CTRL at the (factory calibrated) reset
value or using one of the two boolean properties to set it to the
min/max value - are too coarse.
Implement support for the newly added binding allowing device tree to
specify an nvmem cell containing an appropriate value for this
specific board.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'drivers/net/phy/dp83867.c')
-rw-r--r-- | drivers/net/phy/dp83867.c | 55 |
1 files changed, 49 insertions, 6 deletions
diff --git a/drivers/net/phy/dp83867.c b/drivers/net/phy/dp83867.c index 13dafe7a29bd..1e38039c5c56 100644 --- a/drivers/net/phy/dp83867.c +++ b/drivers/net/phy/dp83867.c @@ -14,6 +14,7 @@ #include <linux/netdevice.h> #include <linux/etherdevice.h> #include <linux/bitfield.h> +#include <linux/nvmem-consumer.h> #include <dt-bindings/net/ti-dp83867.h> @@ -522,6 +523,51 @@ static int dp83867_verify_rgmii_cfg(struct phy_device *phydev) } #if IS_ENABLED(CONFIG_OF_MDIO) +static int dp83867_of_init_io_impedance(struct phy_device *phydev) +{ + struct dp83867_private *dp83867 = phydev->priv; + struct device *dev = &phydev->mdio.dev; + struct device_node *of_node = dev->of_node; + struct nvmem_cell *cell; + u8 *buf, val; + int ret; + + cell = of_nvmem_cell_get(of_node, "io_impedance_ctrl"); + if (IS_ERR(cell)) { + ret = PTR_ERR(cell); + if (ret != -ENOENT) + return phydev_err_probe(phydev, ret, + "failed to get nvmem cell io_impedance_ctrl\n"); + + /* If no nvmem cell, check for the boolean properties. */ + if (of_property_read_bool(of_node, "ti,max-output-impedance")) + dp83867->io_impedance = DP83867_IO_MUX_CFG_IO_IMPEDANCE_MAX; + else if (of_property_read_bool(of_node, "ti,min-output-impedance")) + dp83867->io_impedance = DP83867_IO_MUX_CFG_IO_IMPEDANCE_MIN; + else + dp83867->io_impedance = -1; /* leave at default */ + + return 0; + } + + buf = nvmem_cell_read(cell, NULL); + nvmem_cell_put(cell); + + if (IS_ERR(buf)) + return PTR_ERR(buf); + + val = *buf; + kfree(buf); + + if ((val & DP83867_IO_MUX_CFG_IO_IMPEDANCE_MASK) != val) { + phydev_err(phydev, "nvmem cell 'io_impedance_ctrl' contents out of range\n"); + return -ERANGE; + } + dp83867->io_impedance = val; + + return 0; +} + static int dp83867_of_init(struct phy_device *phydev) { struct dp83867_private *dp83867 = phydev->priv; @@ -549,12 +595,9 @@ static int dp83867_of_init(struct phy_device *phydev) } } - if (of_property_read_bool(of_node, "ti,max-output-impedance")) - dp83867->io_impedance = DP83867_IO_MUX_CFG_IO_IMPEDANCE_MAX; - else if (of_property_read_bool(of_node, "ti,min-output-impedance")) - dp83867->io_impedance = DP83867_IO_MUX_CFG_IO_IMPEDANCE_MIN; - else - dp83867->io_impedance = -1; /* leave at default */ + ret = dp83867_of_init_io_impedance(phydev); + if (ret) + return ret; dp83867->rxctrl_strap_quirk = of_property_read_bool(of_node, "ti,dp83867-rxctrl-strap-quirk"); |