net: pse-pd: Add TI TPS23881 PSE controller driver
authorKory Maincent (Dent Project) <kory.maincent@bootlin.com>
Wed, 17 Apr 2024 14:40:02 +0000 (16:40 +0200)
committerJakub Kicinski <kuba@kernel.org>
Fri, 19 Apr 2024 01:27:39 +0000 (18:27 -0700)
Add a new driver for the TI TPS23881 I2C Power Sourcing Equipment
controller.

Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
Link: https://lore.kernel.org/r/20240417-feature_poe-v9-14-242293fd1900@bootlin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
drivers/net/pse-pd/Kconfig
drivers/net/pse-pd/Makefile
drivers/net/pse-pd/tps23881.c [new file with mode: 0644]

index e3a6ba6..80cf373 100644 (file)
@@ -31,4 +31,13 @@ config PSE_PD692X0
          To compile this driver as a module, choose M here: the
          module will be called pd692x0.
 
+config PSE_TPS23881
+       tristate "TPS23881 PSE controller"
+       depends on I2C
+       help
+         This module provides support for TPS23881 regulator based Ethernet
+         Power Sourcing Equipment.
+
+         To compile this driver as a module, choose M here: the
+         module will be called tps23881.
 endif
index 9c12c4a..9d2898b 100644 (file)
@@ -5,3 +5,4 @@ obj-$(CONFIG_PSE_CONTROLLER) += pse_core.o
 
 obj-$(CONFIG_PSE_REGULATOR) += pse_regulator.o
 obj-$(CONFIG_PSE_PD692X0) += pd692x0.o
+obj-$(CONFIG_PSE_TPS23881) += tps23881.o
diff --git a/drivers/net/pse-pd/tps23881.c b/drivers/net/pse-pd/tps23881.c
new file mode 100644 (file)
index 0000000..98ffbb1
--- /dev/null
@@ -0,0 +1,820 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Driver for the TI TPS23881 PoE PSE Controller driver (I2C bus)
+ *
+ * Copyright (c) 2023 Bootlin, Kory Maincent <kory.maincent@bootlin.com>
+ */
+
+#include <linux/delay.h>
+#include <linux/firmware.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pse-pd/pse.h>
+
+#define TPS23881_MAX_CHANS 8
+
+#define TPS23881_REG_PW_STATUS 0x10
+#define TPS23881_REG_OP_MODE   0x12
+#define TPS23881_OP_MODE_SEMIAUTO      0xaaaa
+#define TPS23881_REG_DIS_EN    0x13
+#define TPS23881_REG_DET_CLA_EN        0x14
+#define TPS23881_REG_GEN_MASK  0x17
+#define TPS23881_REG_NBITACC   BIT(5)
+#define TPS23881_REG_PW_EN     0x19
+#define TPS23881_REG_PORT_MAP  0x26
+#define TPS23881_REG_PORT_POWER        0x29
+#define TPS23881_REG_POEPLUS   0x40
+#define TPS23881_REG_TPON      BIT(0)
+#define TPS23881_REG_FWREV     0x41
+#define TPS23881_REG_DEVID     0x43
+#define TPS23881_REG_SRAM_CTRL 0x60
+#define TPS23881_REG_SRAM_DATA 0x61
+
+struct tps23881_port_desc {
+       u8 chan[2];
+       bool is_4p;
+};
+
+struct tps23881_priv {
+       struct i2c_client *client;
+       struct pse_controller_dev pcdev;
+       struct device_node *np;
+       struct tps23881_port_desc port[TPS23881_MAX_CHANS];
+};
+
+static struct tps23881_priv *to_tps23881_priv(struct pse_controller_dev *pcdev)
+{
+       return container_of(pcdev, struct tps23881_priv, pcdev);
+}
+
+static int tps23881_pi_enable(struct pse_controller_dev *pcdev, int id)
+{
+       struct tps23881_priv *priv = to_tps23881_priv(pcdev);
+       struct i2c_client *client = priv->client;
+       u8 chan;
+       u16 val;
+       int ret;
+
+       if (id >= TPS23881_MAX_CHANS)
+               return -ERANGE;
+
+       ret = i2c_smbus_read_word_data(client, TPS23881_REG_PW_STATUS);
+       if (ret < 0)
+               return ret;
+
+       chan = priv->port[id].chan[0];
+       if (chan < 4)
+               val = (u16)(ret | BIT(chan));
+       else
+               val = (u16)(ret | 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);
+       }
+
+       ret = i2c_smbus_write_word_data(client, TPS23881_REG_PW_EN, val);
+       if (ret)
+               return ret;
+
+       return 0;
+}
+
+static int tps23881_pi_disable(struct pse_controller_dev *pcdev, int id)
+{
+       struct tps23881_priv *priv = to_tps23881_priv(pcdev);
+       struct i2c_client *client = priv->client;
+       u8 chan;
+       u16 val;
+       int ret;
+
+       if (id >= TPS23881_MAX_CHANS)
+               return -ERANGE;
+
+       ret = i2c_smbus_read_word_data(client, TPS23881_REG_PW_STATUS);
+       if (ret < 0)
+               return ret;
+
+       chan = priv->port[id].chan[0];
+       if (chan < 4)
+               val = (u16)(ret | BIT(chan + 4));
+       else
+               val = (u16)(ret | BIT(chan + 8));
+
+       if (priv->port[id].is_4p) {
+               chan = priv->port[id].chan[1];
+               if (chan < 4)
+                       val |= BIT(chan + 4);
+               else
+                       val |= BIT(chan + 8);
+       }
+
+       ret = i2c_smbus_write_word_data(client, TPS23881_REG_PW_EN, val);
+       if (ret)
+               return ret;
+
+       return 0;
+}
+
+static int tps23881_pi_is_enabled(struct pse_controller_dev *pcdev, int id)
+{
+       struct tps23881_priv *priv = to_tps23881_priv(pcdev);
+       struct i2c_client *client = priv->client;
+       bool enabled;
+       u8 chan;
+       int ret;
+
+       ret = i2c_smbus_read_word_data(client, TPS23881_REG_PW_STATUS);
+       if (ret < 0)
+               return ret;
+
+       chan = priv->port[id].chan[0];
+       if (chan < 4)
+               enabled = ret & BIT(chan);
+       else
+               enabled = ret & BIT(chan + 4);
+
+       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));
+       }
+
+       /* Return enabled status only if both channel are on this state */
+       return enabled;
+}
+
+static int tps23881_ethtool_get_status(struct pse_controller_dev *pcdev,
+                                      unsigned long id,
+                                      struct netlink_ext_ack *extack,
+                                      struct pse_control_status *status)
+{
+       struct tps23881_priv *priv = to_tps23881_priv(pcdev);
+       struct i2c_client *client = priv->client;
+       bool enabled, delivering;
+       u8 chan;
+       int ret;
+
+       ret = i2c_smbus_read_word_data(client, TPS23881_REG_PW_STATUS);
+       if (ret < 0)
+               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);
+       }
+
+       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));
+               }
+       }
+
+       /* Return delivering status only if both channel are on this state */
+       if (delivering)
+               status->c33_pw_status = ETHTOOL_C33_PSE_PW_D_STATUS_DELIVERING;
+       else
+               status->c33_pw_status = ETHTOOL_C33_PSE_PW_D_STATUS_DISABLED;
+
+       /* Return enabled status only if both channel are on this state */
+       if (enabled)
+               status->c33_admin_state = ETHTOOL_C33_PSE_ADMIN_STATE_ENABLED;
+       else
+               status->c33_admin_state = ETHTOOL_C33_PSE_ADMIN_STATE_DISABLED;
+
+       return 0;
+}
+
+/* Parse managers subnode into a array of device node */
+static int
+tps23881_get_of_channels(struct tps23881_priv *priv,
+                        struct device_node *chan_node[TPS23881_MAX_CHANS])
+{
+       struct device_node *channels_node, *node;
+       int i, ret;
+
+       if (!priv->np)
+               return -EINVAL;
+
+       channels_node = of_find_node_by_name(priv->np, "channels");
+       if (!channels_node)
+               return -EINVAL;
+
+       for_each_child_of_node(channels_node, node) {
+               u32 chan_id;
+
+               if (!of_node_name_eq(node, "channel"))
+                       continue;
+
+               ret = of_property_read_u32(node, "reg", &chan_id);
+               if (ret) {
+                       ret = -EINVAL;
+                       goto out;
+               }
+
+               if (chan_id >= TPS23881_MAX_CHANS || chan_node[chan_id]) {
+                       dev_err(&priv->client->dev,
+                               "wrong number of port (%d)\n", chan_id);
+                       ret = -EINVAL;
+                       goto out;
+               }
+
+               of_node_get(node);
+               chan_node[chan_id] = node;
+       }
+
+       of_node_put(channels_node);
+       return 0;
+
+out:
+       for (i = 0; i < TPS23881_MAX_CHANS; i++) {
+               of_node_put(chan_node[i]);
+               chan_node[i] = NULL;
+       }
+
+       of_node_put(node);
+       of_node_put(channels_node);
+       return ret;
+}
+
+struct tps23881_port_matrix {
+       u8 pi_id;
+       u8 lgcl_chan[2];
+       u8 hw_chan[2];
+       bool is_4p;
+       bool exist;
+};
+
+static int
+tps23881_match_channel(const struct pse_pi_pairset *pairset,
+                      struct device_node *chan_node[TPS23881_MAX_CHANS])
+{
+       int i;
+
+       /* Look on every channels */
+       for (i = 0; i < TPS23881_MAX_CHANS; i++) {
+               if (pairset->np == chan_node[i])
+                       return i;
+       }
+
+       return -ENODEV;
+}
+
+static bool
+tps23881_is_chan_free(struct tps23881_port_matrix port_matrix[TPS23881_MAX_CHANS],
+                     int chan)
+{
+       int i;
+
+       for (i = 0; i < TPS23881_MAX_CHANS; i++) {
+               if (port_matrix[i].exist &&
+                   (port_matrix[i].hw_chan[0] == chan ||
+                   port_matrix[i].hw_chan[1] == chan))
+                       return false;
+       }
+
+       return true;
+}
+
+/* Fill port matrix with the matching channels */
+static int
+tps23881_match_port_matrix(struct pse_pi *pi, int pi_id,
+                          struct device_node *chan_node[TPS23881_MAX_CHANS],
+                          struct tps23881_port_matrix port_matrix[TPS23881_MAX_CHANS])
+{
+       int ret;
+
+       if (!pi->pairset[0].np)
+               return 0;
+
+       ret = tps23881_match_channel(&pi->pairset[0], chan_node);
+       if (ret < 0)
+               return ret;
+
+       if (!tps23881_is_chan_free(port_matrix, ret)) {
+               pr_err("tps23881: channel %d already used\n", ret);
+               return -ENODEV;
+       }
+
+       port_matrix[pi_id].hw_chan[0] = ret;
+       port_matrix[pi_id].exist = true;
+
+       if (!pi->pairset[1].np)
+               return 0;
+
+       ret = tps23881_match_channel(&pi->pairset[1], chan_node);
+       if (ret < 0)
+               return ret;
+
+       if (!tps23881_is_chan_free(port_matrix, ret)) {
+               pr_err("tps23881: channel %d already used\n", ret);
+               return -ENODEV;
+       }
+
+       if (port_matrix[pi_id].hw_chan[0] / 4 != ret / 4) {
+               pr_err("tps23881: 4-pair PSE can only be set within the same 4 ports group");
+               return -ENODEV;
+       }
+
+       port_matrix[pi_id].hw_chan[1] = ret;
+       port_matrix[pi_id].is_4p = true;
+
+       return 0;
+}
+
+static int
+tps23881_get_unused_chan(struct tps23881_port_matrix port_matrix[TPS23881_MAX_CHANS],
+                        int port_cnt)
+{
+       bool used;
+       int i, j;
+
+       for (i = 0; i < TPS23881_MAX_CHANS; i++) {
+               used = false;
+
+               for (j = 0; j < port_cnt; j++) {
+                       if (port_matrix[j].hw_chan[0] == i) {
+                               used = true;
+                               break;
+                       }
+
+                       if (port_matrix[j].is_4p &&
+                           port_matrix[j].hw_chan[1] == i) {
+                               used = true;
+                               break;
+                       }
+               }
+
+               if (!used)
+                       return i;
+       }
+
+       return -ENODEV;
+}
+
+/* Sort the port matrix to following particular hardware ports matrix
+ * specification of the tps23881. The device has two 4-ports groups and
+ * each 4-pair powered device has to be configured to use two consecutive
+ * logical channel in each 4 ports group (1 and 2 or 3 and 4). Also the
+ * hardware matrix has to be fully configured even with unused chan to be
+ * valid.
+ */
+static int
+tps23881_sort_port_matrix(struct tps23881_port_matrix port_matrix[TPS23881_MAX_CHANS])
+{
+       struct tps23881_port_matrix tmp_port_matrix[TPS23881_MAX_CHANS] = {0};
+       int i, ret, port_cnt = 0, cnt_4ch_grp1 = 0, cnt_4ch_grp2 = 4;
+
+       /* Configure 4p port matrix */
+       for (i = 0; i < TPS23881_MAX_CHANS; i++) {
+               int *cnt;
+
+               if (!port_matrix[i].exist || !port_matrix[i].is_4p)
+                       continue;
+
+               if (port_matrix[i].hw_chan[0] < 4)
+                       cnt = &cnt_4ch_grp1;
+               else
+                       cnt = &cnt_4ch_grp2;
+
+               tmp_port_matrix[port_cnt].exist = true;
+               tmp_port_matrix[port_cnt].is_4p = true;
+               tmp_port_matrix[port_cnt].pi_id = i;
+               tmp_port_matrix[port_cnt].hw_chan[0] = port_matrix[i].hw_chan[0];
+               tmp_port_matrix[port_cnt].hw_chan[1] = port_matrix[i].hw_chan[1];
+
+               /* 4-pair ports have to be configured with consecutive
+                * logical channels 0 and 1, 2 and 3.
+                */
+               tmp_port_matrix[port_cnt].lgcl_chan[0] = (*cnt)++;
+               tmp_port_matrix[port_cnt].lgcl_chan[1] = (*cnt)++;
+
+               port_cnt++;
+       }
+
+       /* Configure 2p port matrix */
+       for (i = 0; i < TPS23881_MAX_CHANS; i++) {
+               int *cnt;
+
+               if (!port_matrix[i].exist || port_matrix[i].is_4p)
+                       continue;
+
+               if (port_matrix[i].hw_chan[0] < 4)
+                       cnt = &cnt_4ch_grp1;
+               else
+                       cnt = &cnt_4ch_grp2;
+
+               tmp_port_matrix[port_cnt].exist = true;
+               tmp_port_matrix[port_cnt].pi_id = i;
+               tmp_port_matrix[port_cnt].lgcl_chan[0] = (*cnt)++;
+               tmp_port_matrix[port_cnt].hw_chan[0] = port_matrix[i].hw_chan[0];
+
+               port_cnt++;
+       }
+
+       /* Complete the rest of the first 4 port group matrix even if
+        * channels are unused
+        */
+       while (cnt_4ch_grp1 < 4) {
+               ret = tps23881_get_unused_chan(tmp_port_matrix, port_cnt);
+               if (ret < 0) {
+                       pr_err("tps23881: port matrix issue, no chan available\n");
+                       return ret;
+               }
+
+               if (port_cnt >= TPS23881_MAX_CHANS) {
+                       pr_err("tps23881: wrong number of channels\n");
+                       return -ENODEV;
+               }
+               tmp_port_matrix[port_cnt].lgcl_chan[0] = cnt_4ch_grp1;
+               tmp_port_matrix[port_cnt].hw_chan[0] = ret;
+               cnt_4ch_grp1++;
+               port_cnt++;
+       }
+
+       /* Complete the rest of the second 4 port group matrix even if
+        * channels are unused
+        */
+       while (cnt_4ch_grp2 < 8) {
+               ret = tps23881_get_unused_chan(tmp_port_matrix, port_cnt);
+               if (ret < 0) {
+                       pr_err("tps23881: port matrix issue, no chan available\n");
+                       return -ENODEV;
+               }
+
+               if (port_cnt >= TPS23881_MAX_CHANS) {
+                       pr_err("tps23881: wrong number of channels\n");
+                       return -ENODEV;
+               }
+               tmp_port_matrix[port_cnt].lgcl_chan[0] = cnt_4ch_grp2;
+               tmp_port_matrix[port_cnt].hw_chan[0] = ret;
+               cnt_4ch_grp2++;
+               port_cnt++;
+       }
+
+       memcpy(port_matrix, tmp_port_matrix, sizeof(tmp_port_matrix));
+
+       return port_cnt;
+}
+
+/* Write port matrix to the hardware port matrix and the software port
+ * matrix.
+ */
+static int
+tps23881_write_port_matrix(struct tps23881_priv *priv,
+                          struct tps23881_port_matrix port_matrix[TPS23881_MAX_CHANS],
+                          int port_cnt)
+{
+       struct i2c_client *client = priv->client;
+       u8 pi_id, lgcl_chan, hw_chan;
+       u16 val = 0;
+       int i, ret;
+
+       for (i = 0; i < port_cnt; i++) {
+               pi_id = port_matrix[i].pi_id;
+               lgcl_chan = port_matrix[i].lgcl_chan[0];
+               hw_chan = port_matrix[i].hw_chan[0] % 4;
+
+               /* Set software port matrix for existing ports */
+               if (port_matrix[i].exist)
+                       priv->port[pi_id].chan[0] = lgcl_chan;
+
+               /* Set hardware port matrix for all ports */
+               val |= hw_chan << (lgcl_chan * 2);
+
+               if (!port_matrix[i].is_4p)
+                       continue;
+
+               lgcl_chan = port_matrix[i].lgcl_chan[1];
+               hw_chan = port_matrix[i].hw_chan[1] % 4;
+
+               /* Set software port matrix for existing ports */
+               if (port_matrix[i].exist) {
+                       priv->port[pi_id].is_4p = true;
+                       priv->port[pi_id].chan[1] = lgcl_chan;
+               }
+
+               /* Set hardware port matrix for all ports */
+               val |= hw_chan << (lgcl_chan * 2);
+       }
+
+       /* Write hardware ports matrix */
+       ret = i2c_smbus_write_word_data(client, TPS23881_REG_PORT_MAP, val);
+       if (ret)
+               return ret;
+
+       return 0;
+}
+
+static int
+tps23881_set_ports_conf(struct tps23881_priv *priv,
+                       struct tps23881_port_matrix port_matrix[TPS23881_MAX_CHANS])
+{
+       struct i2c_client *client = priv->client;
+       int i, ret;
+       u16 val;
+
+       /* Set operating mode */
+       ret = i2c_smbus_write_word_data(client, TPS23881_REG_OP_MODE,
+                                       TPS23881_OP_MODE_SEMIAUTO);
+       if (ret)
+               return ret;
+
+       /* Disable DC disconnect */
+       ret = i2c_smbus_write_word_data(client, TPS23881_REG_DIS_EN, 0x0);
+       if (ret)
+               return ret;
+
+       /* Set port power allocation */
+       val = 0;
+       for (i = 0; i < TPS23881_MAX_CHANS; i++) {
+               if (!port_matrix[i].exist)
+                       continue;
+
+               if (port_matrix[i].is_4p)
+                       val |= 0xf << ((port_matrix[i].lgcl_chan[0] / 2) * 4);
+               else
+                       val |= 0x3 << ((port_matrix[i].lgcl_chan[0] / 2) * 4);
+       }
+       ret = i2c_smbus_write_word_data(client, TPS23881_REG_PORT_POWER, val);
+       if (ret)
+               return ret;
+
+       /* Enable detection and classification */
+       val = 0;
+       for (i = 0; i < TPS23881_MAX_CHANS; i++) {
+               if (!port_matrix[i].exist)
+                       continue;
+
+               val |= BIT(port_matrix[i].lgcl_chan[0]) |
+                      BIT(port_matrix[i].lgcl_chan[0] + 4);
+               if (port_matrix[i].is_4p)
+                       val |= BIT(port_matrix[i].lgcl_chan[1]) |
+                              BIT(port_matrix[i].lgcl_chan[1] + 4);
+       }
+       ret = i2c_smbus_write_word_data(client, TPS23881_REG_DET_CLA_EN, val);
+       if (ret)
+               return ret;
+
+       return 0;
+}
+
+static int
+tps23881_set_ports_matrix(struct tps23881_priv *priv,
+                         struct device_node *chan_node[TPS23881_MAX_CHANS])
+{
+       struct tps23881_port_matrix port_matrix[TPS23881_MAX_CHANS] = {0};
+       int i, ret;
+
+       /* Update with values for every PSE PIs */
+       for (i = 0; i < TPS23881_MAX_CHANS; i++) {
+               ret = tps23881_match_port_matrix(&priv->pcdev.pi[i], i,
+                                                chan_node, port_matrix);
+               if (ret)
+                       return ret;
+       }
+
+       ret = tps23881_sort_port_matrix(port_matrix);
+       if (ret < 0)
+               return ret;
+
+       ret = tps23881_write_port_matrix(priv, port_matrix, ret);
+       if (ret)
+               return ret;
+
+       ret = tps23881_set_ports_conf(priv, port_matrix);
+       if (ret)
+               return ret;
+
+       return 0;
+}
+
+static int tps23881_setup_pi_matrix(struct pse_controller_dev *pcdev)
+{
+       struct device_node *chan_node[TPS23881_MAX_CHANS] = {NULL};
+       struct tps23881_priv *priv = to_tps23881_priv(pcdev);
+       int ret, i;
+
+       ret = tps23881_get_of_channels(priv, chan_node);
+       if (ret < 0) {
+               dev_warn(&priv->client->dev,
+                        "Unable to parse port-matrix, default matrix will be used\n");
+               return 0;
+       }
+
+       ret = tps23881_set_ports_matrix(priv, chan_node);
+
+       for (i = 0; i < TPS23881_MAX_CHANS; i++)
+               of_node_put(chan_node[i]);
+
+       return ret;
+}
+
+static const struct pse_controller_ops tps23881_ops = {
+       .setup_pi_matrix = tps23881_setup_pi_matrix,
+       .pi_enable = tps23881_pi_enable,
+       .pi_disable = tps23881_pi_disable,
+       .pi_is_enabled = tps23881_pi_is_enabled,
+       .ethtool_get_status = tps23881_ethtool_get_status,
+};
+
+static const char fw_parity_name[] = "ti/tps23881/tps23881-parity-14.bin";
+static const char fw_sram_name[] = "ti/tps23881/tps23881-sram-14.bin";
+
+struct tps23881_fw_conf {
+       u8 reg;
+       u8 val;
+};
+
+static const struct tps23881_fw_conf tps23881_fw_parity_conf[] = {
+       {.reg = 0x60, .val = 0x01},
+       {.reg = 0x62, .val = 0x00},
+       {.reg = 0x63, .val = 0x80},
+       {.reg = 0x60, .val = 0xC4},
+       {.reg = 0x1D, .val = 0xBC},
+       {.reg = 0xD7, .val = 0x02},
+       {.reg = 0x91, .val = 0x00},
+       {.reg = 0x90, .val = 0x00},
+       {.reg = 0xD7, .val = 0x00},
+       {.reg = 0x1D, .val = 0x00},
+       { /* sentinel */ }
+};
+
+static const struct tps23881_fw_conf tps23881_fw_sram_conf[] = {
+       {.reg = 0x60, .val = 0xC5},
+       {.reg = 0x62, .val = 0x00},
+       {.reg = 0x63, .val = 0x80},
+       {.reg = 0x60, .val = 0xC0},
+       {.reg = 0x1D, .val = 0xBC},
+       {.reg = 0xD7, .val = 0x02},
+       {.reg = 0x91, .val = 0x00},
+       {.reg = 0x90, .val = 0x00},
+       {.reg = 0xD7, .val = 0x00},
+       {.reg = 0x1D, .val = 0x00},
+       { /* sentinel */ }
+};
+
+static int tps23881_flash_sram_fw_part(struct i2c_client *client,
+                                      const char *fw_name,
+                                      const struct tps23881_fw_conf *fw_conf)
+{
+       const struct firmware *fw = NULL;
+       int i, ret;
+
+       ret = request_firmware(&fw, fw_name, &client->dev);
+       if (ret)
+               return ret;
+
+       dev_dbg(&client->dev, "Flashing %s\n", fw_name);
+
+       /* Prepare device for RAM download */
+       while (fw_conf->reg) {
+               ret = i2c_smbus_write_byte_data(client, fw_conf->reg,
+                                               fw_conf->val);
+               if (ret)
+                       goto out;
+
+               fw_conf++;
+       }
+
+       /* Flash the firmware file */
+       for (i = 0; i < fw->size; i++) {
+               ret = i2c_smbus_write_byte_data(client,
+                                               TPS23881_REG_SRAM_DATA,
+                                               fw->data[i]);
+               if (ret)
+                       goto out;
+       }
+
+out:
+       release_firmware(fw);
+       return ret;
+}
+
+static int tps23881_flash_sram_fw(struct i2c_client *client)
+{
+       int ret;
+
+       ret = tps23881_flash_sram_fw_part(client, fw_parity_name,
+                                         tps23881_fw_parity_conf);
+       if (ret)
+               return ret;
+
+       ret = tps23881_flash_sram_fw_part(client, fw_sram_name,
+                                         tps23881_fw_sram_conf);
+       if (ret)
+               return ret;
+
+       ret = i2c_smbus_write_byte_data(client, TPS23881_REG_SRAM_CTRL, 0x18);
+       if (ret)
+               return ret;
+
+       mdelay(12);
+
+       return 0;
+}
+
+static int tps23881_i2c_probe(struct i2c_client *client)
+{
+       struct device *dev = &client->dev;
+       struct tps23881_priv *priv;
+       int ret;
+       u8 val;
+
+       if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+               dev_err(dev, "i2c check functionality failed\n");
+               return -ENXIO;
+       }
+
+       priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+       if (!priv)
+               return -ENOMEM;
+
+       ret = i2c_smbus_read_byte_data(client, TPS23881_REG_DEVID);
+       if (ret < 0)
+               return ret;
+
+       if (ret != 0x22) {
+               dev_err(dev, "Wrong device ID\n");
+               return -ENXIO;
+       }
+
+       ret = tps23881_flash_sram_fw(client);
+       if (ret < 0)
+               return ret;
+
+       ret = i2c_smbus_read_byte_data(client, TPS23881_REG_FWREV);
+       if (ret < 0)
+               return ret;
+
+       dev_info(&client->dev, "Firmware revision 0x%x\n", ret);
+
+       /* Set configuration B, 16 bit access on a single device address */
+       ret = i2c_smbus_read_byte_data(client, TPS23881_REG_GEN_MASK);
+       if (ret < 0)
+               return ret;
+
+       val = ret | TPS23881_REG_NBITACC;
+       ret = i2c_smbus_write_byte_data(client, TPS23881_REG_GEN_MASK, val);
+       if (ret)
+               return ret;
+
+       priv->client = client;
+       i2c_set_clientdata(client, priv);
+       priv->np = dev->of_node;
+
+       priv->pcdev.owner = THIS_MODULE;
+       priv->pcdev.ops = &tps23881_ops;
+       priv->pcdev.dev = dev;
+       priv->pcdev.types = ETHTOOL_PSE_C33;
+       priv->pcdev.nr_lines = TPS23881_MAX_CHANS;
+       ret = devm_pse_controller_register(dev, &priv->pcdev);
+       if (ret) {
+               return dev_err_probe(dev, ret,
+                                    "failed to register PSE controller\n");
+       }
+
+       return ret;
+}
+
+static const struct i2c_device_id tps23881_id[] = {
+       { "tps23881", 0 },
+       { },
+};
+MODULE_DEVICE_TABLE(i2c, tps23881_id);
+
+static const struct of_device_id tps23881_of_match[] = {
+       { .compatible = "ti,tps23881", },
+       { },
+};
+MODULE_DEVICE_TABLE(of, tps23881_of_match);
+
+static struct i2c_driver tps23881_driver = {
+       .probe          = tps23881_i2c_probe,
+       .id_table       = tps23881_id,
+       .driver         = {
+               .name           = "tps23881",
+               .of_match_table = tps23881_of_match,
+       },
+};
+module_i2c_driver(tps23881_driver);
+
+MODULE_AUTHOR("Kory Maincent <kory.maincent@bootlin.com>");
+MODULE_DESCRIPTION("TI TPS23881 PoE PSE Controller driver");
+MODULE_LICENSE("GPL");