This patch prepares the __mcp251xfd_chip_set_mode() function for PLL support by adding more error checks and diagnostics. Link: https://lore.kernel.org/all/20220207131047.282110-13-mkl@xxxxxxxxxxxxxx Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> --- .../net/can/spi/mcp251xfd/mcp251xfd-core.c | 39 ++++++++++++++----- 1 file changed, 30 insertions(+), 9 deletions(-) diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c b/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c index 154e6c376670..d08e0481df35 100644 --- a/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c +++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c @@ -218,34 +218,55 @@ static int __mcp251xfd_chip_set_mode(const struct mcp251xfd_priv *priv, const u8 mode_req, bool nowait) { - u32 con, con_reqop; + u32 con = 0, con_reqop, osc = 0; + u8 mode; int err; con_reqop = FIELD_PREP(MCP251XFD_REG_CON_REQOP_MASK, mode_req); err = regmap_update_bits(priv->map_reg, MCP251XFD_REG_CON, MCP251XFD_REG_CON_REQOP_MASK, con_reqop); - if (err) + if (err == -EBADMSG) { + netdev_err(priv->ndev, + "Failed to set Requested Operation Mode.\n"); + + return -ENODEV; + } else if (err) { return err; + } if (mode_req == MCP251XFD_REG_CON_MODE_SLEEP || nowait) return 0; err = regmap_read_poll_timeout(priv->map_reg, MCP251XFD_REG_CON, con, + !mcp251xfd_reg_invalid(con) && FIELD_GET(MCP251XFD_REG_CON_OPMOD_MASK, con) == mode_req, MCP251XFD_POLL_SLEEP_US, MCP251XFD_POLL_TIMEOUT_US); - if (err) { - u8 mode = FIELD_GET(MCP251XFD_REG_CON_OPMOD_MASK, con); + if (err != -ETIMEDOUT && err != -EBADMSG) + return err; + + /* Ignore return value. + * Print below error messages, even if this fails. + */ + regmap_read(priv->map_reg, MCP251XFD_REG_OSC, &osc); + if (mcp251xfd_reg_invalid(con)) { netdev_err(priv->ndev, - "Controller failed to enter mode %s Mode (%u) and stays in %s Mode (%u).\n", - mcp251xfd_get_mode_str(mode_req), mode_req, - mcp251xfd_get_mode_str(mode), mode); - return err; + "Failed to read CAN Control Register (con=0x%08x, osc=0x%08x).\n", + con, osc); + + return -ENODEV; } - return 0; + mode = FIELD_GET(MCP251XFD_REG_CON_OPMOD_MASK, con); + netdev_err(priv->ndev, + "Controller failed to enter mode %s Mode (%u) and stays in %s Mode (%u) (con=0x%08x, osc=0x%08x).\n", + mcp251xfd_get_mode_str(mode_req), mode_req, + mcp251xfd_get_mode_str(mode), mode, + con, osc); + + return -ETIMEDOUT; } static inline int -- 2.34.1
