From: Kory Maincent (Dent Project) <kory.maincent@bootlin.com>
This driver frequently follows a pattern where two registers are read or
written in a single operation, followed by calculating the bit offset for
a specific channel.
Introduce helpers to streamline this process and reduce code redundancy,
making the codebase cleaner and more maintainable.
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
---
Thanks to Oleksij for the design of the helpers functions.
Change in v3:
- Small fix: use chan >= 4 instead of chan > 4;
Change in v2:
- New patch
---
drivers/net/pse-pd/tps23881.c | 107 +++++++++++++++++++++++++++---------------
1 file changed, 69 insertions(+), 38 deletions(-)
diff --git a/drivers/net/pse-pd/tps23881.c b/drivers/net/pse-pd/tps23881.c
index 20eab9857817..6fd76ecb2961 100644
--- a/drivers/net/pse-pd/tps23881.c
+++ b/drivers/net/pse-pd/tps23881.c
@@ -53,6 +53,55 @@ static struct tps23881_priv *to_tps23881_priv(struct pse_controller_dev *pcdev)
return container_of(pcdev, struct tps23881_priv, pcdev);
}
+/*
+ * Helper to extract a value from a u16 register value, which is made of two
+ * u8 registers. The function calculates the bit offset based on the channel
+ * and extracts the relevant bits using a provided field mask.
+ *
+ * @param reg_val: The u16 register value (composed of two u8 registers).
+ * @param chan: The channel number (0-7).
+ * @param field_offset: The base bit offset to apply (e.g., 0 or 4).
+ * @param field_mask: The mask to apply to extract the required bits.
+ * @return: The extracted value for the specific channel.
+ */
+static u16 tps23881_calc_val(u16 reg_val, u8 chan, u8 field_offset,
+ u16 field_mask)
+{
+ if (chan >= 4)
+ reg_val >>= 8;
+
+ return (reg_val >> field_offset) & field_mask;
+}
+
+/*
+ * Helper to combine individual channel values into a u16 register value.
+ * The function sets the value for a specific channel in the appropriate
+ * position.
+ *
+ * @param reg_val: The current u16 register value.
+ * @param chan: The channel number (0-7).
+ * @param field_offset: The base bit offset to apply (e.g., 0 or 4).
+ * @param field_mask: The mask to apply for the field (e.g., 0x0F).
+ * @param field_val: The value to set for the specific channel (masked by
+ * field_mask).
+ * @return: The updated u16 register value with the channel value set.
+ */
+static u16 tps23881_set_val(u16 reg_val, u8 chan, u8 field_offset,
+ u16 field_mask, u16 field_val)
+{
+ field_val &= field_mask;
+
+ if (chan < 4) {
+ reg_val &= ~(field_mask << field_offset);
+ reg_val |= (field_val << field_offset);
+ } else {
+ reg_val &= ~(field_mask << (field_offset + 8));
+ reg_val |= (field_val << (field_offset + 8));
+ }
+
+ return reg_val;
+}
+
static int tps23881_pi_enable(struct pse_controller_dev *pcdev, int id)
{
struct tps23881_priv *priv = to_tps23881_priv(pcdev);
@@ -69,17 +118,12 @@ static int tps23881_pi_enable(struct pse_controller_dev *pcdev, int id)
return ret;
chan = priv->port[id].chan[0];
- if (chan < 4)
- val = (u16)(ret | BIT(chan));
- else
- val = (u16)(ret | BIT(chan + 4));
+ val = tps23881_set_val(ret, chan, 0, BIT(chan % 4), BIT(chan % 4));
if (priv->port[id].is_4p) {
chan = priv->port[id].chan[1];
- if (chan < 4)
- val |= BIT(chan);
- else
- val |= BIT(chan + 4);
+ val = tps23881_set_val(val, chan, 0, BIT(chan % 4),
+ BIT(chan % 4));
}
ret = i2c_smbus_write_word_data(client, TPS23881_REG_PW_EN, val);
@@ -105,17 +149,12 @@ static int tps23881_pi_disable(struct pse_controller_dev *pcdev, int id)
return ret;
chan = priv->port[id].chan[0];
- if (chan < 4)
- val = (u16)(ret | BIT(chan + 4));
- else
- val = (u16)(ret | BIT(chan + 8));
+ val = tps23881_set_val(ret, chan, 4, BIT(chan % 4), BIT(chan % 4));
if (priv->port[id].is_4p) {
chan = priv->port[id].chan[1];
- if (chan < 4)
- val |= BIT(chan + 4);
- else
- val |= BIT(chan + 8);
+ val = tps23881_set_val(val, chan, 4, BIT(chan % 4),
+ BIT(chan % 4));
}
return i2c_smbus_write_word_data(client, TPS23881_REG_PW_EN, val);
@@ -127,6 +166,7 @@ static int tps23881_pi_is_enabled(struct pse_controller_dev *pcdev, int id)
struct i2c_client *client = priv->client;
bool enabled;
u8 chan;
+ u16 val;
int ret;
ret = i2c_smbus_read_word_data(client, TPS23881_REG_PW_STATUS);
@@ -134,17 +174,13 @@ static int tps23881_pi_is_enabled(struct pse_controller_dev *pcdev, int id)
return ret;
chan = priv->port[id].chan[0];
- if (chan < 4)
- enabled = ret & BIT(chan);
- else
- enabled = ret & BIT(chan + 4);
+ val = tps23881_calc_val(ret, chan, 0, BIT(chan % 4));
+ enabled = !!(val);
if (priv->port[id].is_4p) {
chan = priv->port[id].chan[1];
- if (chan < 4)
- enabled &= !!(ret & BIT(chan));
- else
- enabled &= !!(ret & BIT(chan + 4));
+ val = tps23881_calc_val(ret, chan, 0, BIT(chan % 4));
+ enabled &= !!(val);
}
/* Return enabled status only if both channel are on this state */
@@ -160,6 +196,7 @@ static int tps23881_ethtool_get_status(struct pse_controller_dev *pcdev,
struct i2c_client *client = priv->client;
bool enabled, delivering;
u8 chan;
+ u16 val;
int ret;
ret = i2c_smbus_read_word_data(client, TPS23881_REG_PW_STATUS);
@@ -167,23 +204,17 @@ static int tps23881_ethtool_get_status(struct pse_controller_dev *pcdev,
return ret;
chan = priv->port[id].chan[0];
- if (chan < 4) {
- enabled = ret & BIT(chan);
- delivering = ret & BIT(chan + 4);
- } else {
- enabled = ret & BIT(chan + 4);
- delivering = ret & BIT(chan + 8);
- }
+ val = tps23881_calc_val(ret, chan, 0, BIT(chan % 4));
+ enabled = !!(val);
+ val = tps23881_calc_val(ret, chan, 4, BIT(chan % 4));
+ delivering = !!(val);
if (priv->port[id].is_4p) {
chan = priv->port[id].chan[1];
- if (chan < 4) {
- enabled &= !!(ret & BIT(chan));
- delivering &= !!(ret & BIT(chan + 4));
- } else {
- enabled &= !!(ret & BIT(chan + 4));
- delivering &= !!(ret & BIT(chan + 8));
- }
+ val = tps23881_calc_val(ret, chan, 0, BIT(chan % 4));
+ enabled &= !!(val);
+ val = tps23881_calc_val(ret, chan, 4, BIT(chan % 4));
+ delivering &= !!(val);
}
/* Return delivering status only if both channel are on this state */
--
2.34.1