forked from mirrors/linux
mctp i3c: MCTP I3C driver
Provides MCTP network transport over an I3C bus, as specified in DMTF DSP0233. Each I3C bus (with "mctp-controller" devicetree property) gets an "mctpi3cX" net device created. I3C devices are reachable as remote endpoints through that net device. Link layer addressing uses the I3C PID as a fixed hardware address for neighbour table entries. The driver matches I3C devices that have the MIPI assigned DCR 0xCC for MCTP. Signed-off-by: Matt Johnston <matt@codeconstruct.com.au> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This commit is contained in:
Matt Johnston
Paolo Abeni
parent
0ac6486e5c
commit
c8755b29b5
3 changed files with 765 additions and 0 deletions
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@ -33,6 +33,15 @@ config MCTP_TRANSPORT_I2C
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from DMTF specification DSP0237. A MCTP protocol network device is
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created for each I2C bus that has been assigned a mctp-i2c device.
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config MCTP_TRANSPORT_I3C
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tristate "MCTP I3C transport"
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depends on I3C
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help
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Provides a driver to access MCTP devices over I3C transport,
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from DMTF specification DSP0233.
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A MCTP protocol network device is created for each I3C bus
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having a "mctp-controller" devicetree property.
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endmenu
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endif
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@ -1,2 +1,3 @@
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obj-$(CONFIG_MCTP_SERIAL) += mctp-serial.o
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obj-$(CONFIG_MCTP_TRANSPORT_I2C) += mctp-i2c.o
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obj-$(CONFIG_MCTP_TRANSPORT_I3C) += mctp-i3c.o
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755
drivers/net/mctp/mctp-i3c.c
Normal file
755
drivers/net/mctp/mctp-i3c.c
Normal file
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@ -0,0 +1,755 @@
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// SPDX-License-Identifier: GPL-2.0
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/*
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* Implements DMTF specification
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* "DSP0233 Management Component Transport Protocol (MCTP) I3C Transport
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* Binding"
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* https://www.dmtf.org/sites/default/files/standards/documents/DSP0233_1.0.0.pdf
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*
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* Copyright (c) 2023 Code Construct
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*/
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#include <linux/module.h>
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#include <linux/netdevice.h>
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#include <linux/i3c/device.h>
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#include <linux/i3c/master.h>
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#include <linux/if_arp.h>
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#include <asm/unaligned.h>
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#include <net/mctp.h>
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#include <net/mctpdevice.h>
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#define MCTP_I3C_MAXBUF 65536
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/* 48 bit Provisioned Id */
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#define PID_SIZE 6
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/* 64 byte payload, 4 byte MCTP header */
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static const int MCTP_I3C_MINMTU = 64 + 4;
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/* One byte less to allow for the PEC */
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static const int MCTP_I3C_MAXMTU = MCTP_I3C_MAXBUF - 1;
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/* 4 byte MCTP header, no data, 1 byte PEC */
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static const int MCTP_I3C_MINLEN = 4 + 1;
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/* Sufficient for 64kB at min mtu */
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static const int MCTP_I3C_TX_QUEUE_LEN = 1100;
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/* Somewhat arbitrary */
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static const int MCTP_I3C_IBI_SLOTS = 8;
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/* Mandatory Data Byte in an IBI, from DSP0233 */
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#define I3C_MDB_MCTP 0xAE
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/* From MIPI Device Characteristics Register (DCR) Assignments */
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#define I3C_DCR_MCTP 0xCC
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static const char *MCTP_I3C_OF_PROP = "mctp-controller";
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/* List of mctp_i3c_busdev */
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static LIST_HEAD(busdevs);
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/* Protects busdevs, as well as mctp_i3c_bus.devs lists */
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static DEFINE_MUTEX(busdevs_lock);
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struct mctp_i3c_bus {
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struct net_device *ndev;
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struct task_struct *tx_thread;
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wait_queue_head_t tx_wq;
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/* tx_lock protects tx_skb and devs */
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spinlock_t tx_lock;
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/* Next skb to transmit */
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struct sk_buff *tx_skb;
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/* Scratch buffer for xmit */
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u8 tx_scratch[MCTP_I3C_MAXBUF];
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/* Element of busdevs */
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struct list_head list;
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/* Provisioned ID of our controller */
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u64 pid;
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struct i3c_bus *bus;
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/* Head of mctp_i3c_device.list. Protected by busdevs_lock */
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struct list_head devs;
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};
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struct mctp_i3c_device {
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struct i3c_device *i3c;
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struct mctp_i3c_bus *mbus;
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struct list_head list; /* Element of mctp_i3c_bus.devs */
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/* Held while tx_thread is using this device */
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struct mutex lock;
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/* Whether BCR indicates MDB is present in IBI */
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bool have_mdb;
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/* I3C dynamic address */
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u8 addr;
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/* Maximum read length */
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u16 mrl;
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/* Maximum write length */
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u16 mwl;
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/* Provisioned ID */
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u64 pid;
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};
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/* We synthesise a mac header using the Provisioned ID.
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* Used to pass dest to mctp_i3c_start_xmit.
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*/
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struct mctp_i3c_internal_hdr {
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u8 dest[PID_SIZE];
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u8 source[PID_SIZE];
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} __packed;
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static int mctp_i3c_read(struct mctp_i3c_device *mi)
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{
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struct i3c_priv_xfer xfer = { .rnw = 1, .len = mi->mrl };
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struct net_device_stats *stats = &mi->mbus->ndev->stats;
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struct mctp_i3c_internal_hdr *ihdr = NULL;
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struct sk_buff *skb = NULL;
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struct mctp_skb_cb *cb;
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int net_status, rc;
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u8 pec, addr;
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skb = netdev_alloc_skb(mi->mbus->ndev,
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mi->mrl + sizeof(struct mctp_i3c_internal_hdr));
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if (!skb) {
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stats->rx_dropped++;
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rc = -ENOMEM;
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goto err;
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}
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skb->protocol = htons(ETH_P_MCTP);
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/* Create a header for internal use */
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skb_reset_mac_header(skb);
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ihdr = skb_put(skb, sizeof(struct mctp_i3c_internal_hdr));
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put_unaligned_be48(mi->pid, ihdr->source);
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put_unaligned_be48(mi->mbus->pid, ihdr->dest);
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skb_pull(skb, sizeof(struct mctp_i3c_internal_hdr));
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xfer.data.in = skb_put(skb, mi->mrl);
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rc = i3c_device_do_priv_xfers(mi->i3c, &xfer, 1);
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if (rc < 0)
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goto err;
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if (WARN_ON_ONCE(xfer.len > mi->mrl)) {
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/* Bad i3c bus driver */
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rc = -EIO;
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goto err;
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}
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if (xfer.len < MCTP_I3C_MINLEN) {
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stats->rx_length_errors++;
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rc = -EIO;
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goto err;
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}
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/* check PEC, including address byte */
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addr = mi->addr << 1 | 1;
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pec = i2c_smbus_pec(0, &addr, 1);
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pec = i2c_smbus_pec(pec, xfer.data.in, xfer.len - 1);
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if (pec != ((u8 *)xfer.data.in)[xfer.len - 1]) {
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stats->rx_crc_errors++;
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rc = -EINVAL;
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goto err;
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}
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/* Remove PEC */
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skb_trim(skb, xfer.len - 1);
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cb = __mctp_cb(skb);
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cb->halen = PID_SIZE;
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put_unaligned_be48(mi->pid, cb->haddr);
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net_status = netif_rx(skb);
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if (net_status == NET_RX_SUCCESS) {
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stats->rx_packets++;
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stats->rx_bytes += xfer.len - 1;
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} else {
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stats->rx_dropped++;
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}
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return 0;
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err:
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kfree_skb(skb);
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return rc;
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}
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static void mctp_i3c_ibi_handler(struct i3c_device *i3c,
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const struct i3c_ibi_payload *payload)
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{
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struct mctp_i3c_device *mi = i3cdev_get_drvdata(i3c);
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if (WARN_ON_ONCE(!mi))
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return;
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if (mi->have_mdb) {
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if (payload->len > 0) {
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if (((u8 *)payload->data)[0] != I3C_MDB_MCTP) {
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/* Not a mctp-i3c interrupt, ignore it */
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return;
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}
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} else {
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/* The BCR advertised a Mandatory Data Byte but the
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* device didn't send one.
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*/
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dev_warn_once(i3cdev_to_dev(i3c), "IBI with missing MDB");
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}
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}
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mctp_i3c_read(mi);
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}
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static int mctp_i3c_setup(struct mctp_i3c_device *mi)
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{
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const struct i3c_ibi_setup ibi = {
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.max_payload_len = 1,
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.num_slots = MCTP_I3C_IBI_SLOTS,
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.handler = mctp_i3c_ibi_handler,
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};
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struct i3c_device_info info;
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int rc;
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i3c_device_get_info(mi->i3c, &info);
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mi->have_mdb = info.bcr & BIT(2);
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mi->addr = info.dyn_addr;
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mi->mwl = info.max_write_len;
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mi->mrl = info.max_read_len;
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mi->pid = info.pid;
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rc = i3c_device_request_ibi(mi->i3c, &ibi);
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if (rc == -ENOTSUPP) {
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/* This driver only supports In-Band Interrupt mode.
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* Support for Polling Mode could be added if required.
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* (ENOTSUPP is from the i3c layer, not EOPNOTSUPP).
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*/
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dev_warn(i3cdev_to_dev(mi->i3c),
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"Failed, bus driver doesn't support In-Band Interrupts");
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goto err;
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} else if (rc < 0) {
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dev_err(i3cdev_to_dev(mi->i3c),
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"Failed requesting IBI (%d)\n", rc);
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goto err;
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}
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rc = i3c_device_enable_ibi(mi->i3c);
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if (rc < 0) {
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/* Assume a driver supporting request_ibi also
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* supports enable_ibi.
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*/
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dev_err(i3cdev_to_dev(mi->i3c), "Failed enabling IBI (%d)\n", rc);
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goto err_free_ibi;
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}
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return 0;
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err_free_ibi:
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i3c_device_free_ibi(mi->i3c);
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err:
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return rc;
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}
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/* Adds a new MCTP i3c_device to a bus */
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static int mctp_i3c_add_device(struct mctp_i3c_bus *mbus,
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struct i3c_device *i3c)
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__must_hold(&busdevs_lock)
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{
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struct mctp_i3c_device *mi = NULL;
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int rc;
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mi = kzalloc(sizeof(*mi), GFP_KERNEL);
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if (!mi) {
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rc = -ENOMEM;
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goto err;
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}
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mi->mbus = mbus;
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mi->i3c = i3c;
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mutex_init(&mi->lock);
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list_add(&mi->list, &mbus->devs);
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i3cdev_set_drvdata(i3c, mi);
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rc = mctp_i3c_setup(mi);
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if (rc < 0)
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goto err_free;
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return 0;
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err_free:
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list_del(&mi->list);
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kfree(mi);
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err:
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dev_warn(i3cdev_to_dev(i3c), "Error adding mctp-i3c device, %d\n", rc);
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return rc;
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}
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static int mctp_i3c_probe(struct i3c_device *i3c)
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{
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struct mctp_i3c_bus *b = NULL, *mbus = NULL;
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/* Look for a known bus */
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mutex_lock(&busdevs_lock);
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list_for_each_entry(b, &busdevs, list)
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if (b->bus == i3c->bus) {
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mbus = b;
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break;
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}
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mutex_unlock(&busdevs_lock);
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if (!mbus) {
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/* probably no "mctp-controller" property on the i3c bus */
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return -ENODEV;
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}
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return mctp_i3c_add_device(mbus, i3c);
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}
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static void mctp_i3c_remove_device(struct mctp_i3c_device *mi)
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__must_hold(&busdevs_lock)
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{
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/* Ensure the tx thread isn't using the device */
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mutex_lock(&mi->lock);
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/* Counterpart of mctp_i3c_setup */
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i3c_device_disable_ibi(mi->i3c);
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i3c_device_free_ibi(mi->i3c);
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/* Counterpart of mctp_i3c_add_device */
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i3cdev_set_drvdata(mi->i3c, NULL);
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list_del(&mi->list);
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/* Safe to unlock after removing from the list */
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mutex_unlock(&mi->lock);
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kfree(mi);
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}
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static void mctp_i3c_remove(struct i3c_device *i3c)
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{
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struct mctp_i3c_device *mi = i3cdev_get_drvdata(i3c);
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/* We my have received a Bus Remove notify prior to device remove,
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* so mi will already be removed.
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*/
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if (!mi)
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return;
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mutex_lock(&busdevs_lock);
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mctp_i3c_remove_device(mi);
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mutex_unlock(&busdevs_lock);
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}
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/* Returns the device for an address, with mi->lock held */
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static struct mctp_i3c_device *
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mctp_i3c_lookup(struct mctp_i3c_bus *mbus, u64 pid)
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{
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struct mctp_i3c_device *mi = NULL, *ret = NULL;
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mutex_lock(&busdevs_lock);
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list_for_each_entry(mi, &mbus->devs, list)
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if (mi->pid == pid) {
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ret = mi;
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mutex_lock(&mi->lock);
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break;
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}
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mutex_unlock(&busdevs_lock);
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return ret;
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}
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static void mctp_i3c_xmit(struct mctp_i3c_bus *mbus, struct sk_buff *skb)
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{
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struct net_device_stats *stats = &mbus->ndev->stats;
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struct i3c_priv_xfer xfer = { .rnw = false };
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struct mctp_i3c_internal_hdr *ihdr = NULL;
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struct mctp_i3c_device *mi = NULL;
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unsigned int data_len;
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u8 *data = NULL;
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u8 addr, pec;
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int rc = 0;
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u64 pid;
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skb_pull(skb, sizeof(struct mctp_i3c_internal_hdr));
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data_len = skb->len;
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ihdr = (void *)skb_mac_header(skb);
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pid = get_unaligned_be48(ihdr->dest);
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mi = mctp_i3c_lookup(mbus, pid);
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if (!mi) {
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/* I3C endpoint went away after the packet was enqueued? */
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stats->tx_dropped++;
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goto out;
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}
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if (WARN_ON_ONCE(data_len + 1 > MCTP_I3C_MAXBUF))
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goto out;
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if (data_len + 1 > (unsigned int)mi->mwl) {
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/* Route MTU was larger than supported by the endpoint */
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stats->tx_dropped++;
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goto out;
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}
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/* Need a linear buffer with space for the PEC */
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xfer.len = data_len + 1;
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if (skb_tailroom(skb) >= 1) {
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skb_put(skb, 1);
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data = skb->data;
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} else {
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/* Otherwise need to copy the buffer */
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skb_copy_bits(skb, 0, mbus->tx_scratch, skb->len);
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data = mbus->tx_scratch;
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}
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/* PEC calculation */
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addr = mi->addr << 1;
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pec = i2c_smbus_pec(0, &addr, 1);
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pec = i2c_smbus_pec(pec, data, data_len);
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data[data_len] = pec;
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xfer.data.out = data;
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rc = i3c_device_do_priv_xfers(mi->i3c, &xfer, 1);
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if (rc == 0) {
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stats->tx_bytes += data_len;
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stats->tx_packets++;
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} else {
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stats->tx_errors++;
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}
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out:
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if (mi)
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mutex_unlock(&mi->lock);
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}
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static int mctp_i3c_tx_thread(void *data)
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{
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struct mctp_i3c_bus *mbus = data;
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struct sk_buff *skb;
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for (;;) {
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if (kthread_should_stop())
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break;
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spin_lock_bh(&mbus->tx_lock);
|
||||
skb = mbus->tx_skb;
|
||||
mbus->tx_skb = NULL;
|
||||
spin_unlock_bh(&mbus->tx_lock);
|
||||
|
||||
if (netif_queue_stopped(mbus->ndev))
|
||||
netif_wake_queue(mbus->ndev);
|
||||
|
||||
if (skb) {
|
||||
mctp_i3c_xmit(mbus, skb);
|
||||
kfree_skb(skb);
|
||||
} else {
|
||||
wait_event_idle(mbus->tx_wq,
|
||||
mbus->tx_skb || kthread_should_stop());
|
||||
}
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static netdev_tx_t mctp_i3c_start_xmit(struct sk_buff *skb,
|
||||
struct net_device *ndev)
|
||||
{
|
||||
struct mctp_i3c_bus *mbus = netdev_priv(ndev);
|
||||
netdev_tx_t ret;
|
||||
|
||||
spin_lock(&mbus->tx_lock);
|
||||
netif_stop_queue(ndev);
|
||||
if (mbus->tx_skb) {
|
||||
dev_warn_ratelimited(&ndev->dev, "TX with queue stopped");
|
||||
ret = NETDEV_TX_BUSY;
|
||||
} else {
|
||||
mbus->tx_skb = skb;
|
||||
ret = NETDEV_TX_OK;
|
||||
}
|
||||
spin_unlock(&mbus->tx_lock);
|
||||
|
||||
if (ret == NETDEV_TX_OK)
|
||||
wake_up(&mbus->tx_wq);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static void mctp_i3c_bus_free(struct mctp_i3c_bus *mbus)
|
||||
__must_hold(&busdevs_lock)
|
||||
{
|
||||
struct mctp_i3c_device *mi = NULL, *tmp = NULL;
|
||||
|
||||
if (mbus->tx_thread) {
|
||||
kthread_stop(mbus->tx_thread);
|
||||
mbus->tx_thread = NULL;
|
||||
}
|
||||
|
||||
/* Remove any child devices */
|
||||
list_for_each_entry_safe(mi, tmp, &mbus->devs, list) {
|
||||
mctp_i3c_remove_device(mi);
|
||||
}
|
||||
|
||||
kfree_skb(mbus->tx_skb);
|
||||
list_del(&mbus->list);
|
||||
}
|
||||
|
||||
static void mctp_i3c_ndo_uninit(struct net_device *ndev)
|
||||
{
|
||||
struct mctp_i3c_bus *mbus = netdev_priv(ndev);
|
||||
|
||||
/* Perform cleanup here to ensure there are no remaining references */
|
||||
mctp_i3c_bus_free(mbus);
|
||||
}
|
||||
|
||||
static int mctp_i3c_header_create(struct sk_buff *skb, struct net_device *dev,
|
||||
unsigned short type, const void *daddr,
|
||||
const void *saddr, unsigned int len)
|
||||
{
|
||||
struct mctp_i3c_internal_hdr *ihdr;
|
||||
|
||||
skb_push(skb, sizeof(struct mctp_i3c_internal_hdr));
|
||||
skb_reset_mac_header(skb);
|
||||
ihdr = (void *)skb_mac_header(skb);
|
||||
memcpy(ihdr->dest, daddr, PID_SIZE);
|
||||
memcpy(ihdr->source, saddr, PID_SIZE);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static const struct net_device_ops mctp_i3c_ops = {
|
||||
.ndo_start_xmit = mctp_i3c_start_xmit,
|
||||
.ndo_uninit = mctp_i3c_ndo_uninit,
|
||||
};
|
||||
|
||||
static const struct header_ops mctp_i3c_headops = {
|
||||
.create = mctp_i3c_header_create,
|
||||
};
|
||||
|
||||
static void mctp_i3c_net_setup(struct net_device *dev)
|
||||
{
|
||||
dev->type = ARPHRD_MCTP;
|
||||
|
||||
dev->mtu = MCTP_I3C_MAXMTU;
|
||||
dev->min_mtu = MCTP_I3C_MINMTU;
|
||||
dev->max_mtu = MCTP_I3C_MAXMTU;
|
||||
dev->tx_queue_len = MCTP_I3C_TX_QUEUE_LEN;
|
||||
|
||||
dev->hard_header_len = sizeof(struct mctp_i3c_internal_hdr);
|
||||
dev->addr_len = PID_SIZE;
|
||||
|
||||
dev->netdev_ops = &mctp_i3c_ops;
|
||||
dev->header_ops = &mctp_i3c_headops;
|
||||
}
|
||||
|
||||
static bool mctp_i3c_is_mctp_controller(struct i3c_bus *bus)
|
||||
{
|
||||
struct i3c_dev_desc *master = bus->cur_master;
|
||||
|
||||
if (!master)
|
||||
return false;
|
||||
|
||||
return of_property_read_bool(master->common.master->dev.of_node,
|
||||
MCTP_I3C_OF_PROP);
|
||||
}
|
||||
|
||||
/* Returns the Provisioned Id of a local bus master */
|
||||
static int mctp_i3c_bus_local_pid(struct i3c_bus *bus, u64 *ret_pid)
|
||||
{
|
||||
struct i3c_dev_desc *master;
|
||||
|
||||
master = bus->cur_master;
|
||||
if (WARN_ON_ONCE(!master))
|
||||
return -ENOENT;
|
||||
*ret_pid = master->info.pid;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Returns an ERR_PTR on failure */
|
||||
static struct mctp_i3c_bus *mctp_i3c_bus_add(struct i3c_bus *bus)
|
||||
__must_hold(&busdevs_lock)
|
||||
{
|
||||
struct mctp_i3c_bus *mbus = NULL;
|
||||
struct net_device *ndev = NULL;
|
||||
char namebuf[IFNAMSIZ];
|
||||
u8 addr[PID_SIZE];
|
||||
int rc;
|
||||
|
||||
if (!mctp_i3c_is_mctp_controller(bus))
|
||||
return ERR_PTR(-ENOENT);
|
||||
|
||||
snprintf(namebuf, sizeof(namebuf), "mctpi3c%d", bus->id);
|
||||
ndev = alloc_netdev(sizeof(*mbus), namebuf, NET_NAME_ENUM,
|
||||
mctp_i3c_net_setup);
|
||||
if (!ndev) {
|
||||
rc = -ENOMEM;
|
||||
goto err;
|
||||
}
|
||||
|
||||
mbus = netdev_priv(ndev);
|
||||
mbus->ndev = ndev;
|
||||
mbus->bus = bus;
|
||||
INIT_LIST_HEAD(&mbus->devs);
|
||||
list_add(&mbus->list, &busdevs);
|
||||
|
||||
rc = mctp_i3c_bus_local_pid(bus, &mbus->pid);
|
||||
if (rc < 0) {
|
||||
dev_err(&ndev->dev, "No I3C PID available\n");
|
||||
goto err_free_uninit;
|
||||
}
|
||||
put_unaligned_be48(mbus->pid, addr);
|
||||
dev_addr_set(ndev, addr);
|
||||
|
||||
init_waitqueue_head(&mbus->tx_wq);
|
||||
spin_lock_init(&mbus->tx_lock);
|
||||
mbus->tx_thread = kthread_run(mctp_i3c_tx_thread, mbus,
|
||||
"%s/tx", ndev->name);
|
||||
if (IS_ERR(mbus->tx_thread)) {
|
||||
dev_warn(&ndev->dev, "Error creating thread: %pe\n",
|
||||
mbus->tx_thread);
|
||||
rc = PTR_ERR(mbus->tx_thread);
|
||||
mbus->tx_thread = NULL;
|
||||
goto err_free_uninit;
|
||||
}
|
||||
|
||||
rc = mctp_register_netdev(ndev, NULL);
|
||||
if (rc < 0) {
|
||||
dev_warn(&ndev->dev, "netdev register failed: %d\n", rc);
|
||||
goto err_free_netdev;
|
||||
}
|
||||
return mbus;
|
||||
|
||||
err_free_uninit:
|
||||
/* uninit will not get called if a netdev has not been registered,
|
||||
* so we perform the same mbus cleanup manually.
|
||||
*/
|
||||
mctp_i3c_bus_free(mbus);
|
||||
|
||||
err_free_netdev:
|
||||
free_netdev(ndev);
|
||||
|
||||
err:
|
||||
return ERR_PTR(rc);
|
||||
}
|
||||
|
||||
static void mctp_i3c_bus_remove(struct mctp_i3c_bus *mbus)
|
||||
__must_hold(&busdevs_lock)
|
||||
{
|
||||
/* Unregister calls through to ndo_uninit -> mctp_i3c_bus_free() */
|
||||
mctp_unregister_netdev(mbus->ndev);
|
||||
|
||||
free_netdev(mbus->ndev);
|
||||
/* mbus is deallocated */
|
||||
}
|
||||
|
||||
/* Removes all mctp-i3c busses */
|
||||
static void mctp_i3c_bus_remove_all(void)
|
||||
{
|
||||
struct mctp_i3c_bus *mbus = NULL, *tmp = NULL;
|
||||
|
||||
mutex_lock(&busdevs_lock);
|
||||
list_for_each_entry_safe(mbus, tmp, &busdevs, list) {
|
||||
mctp_i3c_bus_remove(mbus);
|
||||
}
|
||||
mutex_unlock(&busdevs_lock);
|
||||
}
|
||||
|
||||
/* Adds a i3c_bus if it isn't already in the busdevs list.
|
||||
* Suitable as an i3c_for_each_bus_locked callback.
|
||||
*/
|
||||
static int mctp_i3c_bus_add_new(struct i3c_bus *bus, void *data)
|
||||
{
|
||||
struct mctp_i3c_bus *mbus = NULL, *tmp = NULL;
|
||||
bool exists = false;
|
||||
|
||||
mutex_lock(&busdevs_lock);
|
||||
list_for_each_entry_safe(mbus, tmp, &busdevs, list)
|
||||
if (mbus->bus == bus)
|
||||
exists = true;
|
||||
|
||||
/* It is OK for a bus to already exist. That can occur due to
|
||||
* the race in mod_init between notifier and for_each_bus
|
||||
*/
|
||||
if (!exists)
|
||||
mctp_i3c_bus_add(bus);
|
||||
mutex_unlock(&busdevs_lock);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void mctp_i3c_notify_bus_remove(struct i3c_bus *bus)
|
||||
{
|
||||
struct mctp_i3c_bus *mbus = NULL, *tmp;
|
||||
|
||||
mutex_lock(&busdevs_lock);
|
||||
list_for_each_entry_safe(mbus, tmp, &busdevs, list)
|
||||
if (mbus->bus == bus)
|
||||
mctp_i3c_bus_remove(mbus);
|
||||
mutex_unlock(&busdevs_lock);
|
||||
}
|
||||
|
||||
static int mctp_i3c_notifier_call(struct notifier_block *nb,
|
||||
unsigned long action, void *data)
|
||||
{
|
||||
switch (action) {
|
||||
case I3C_NOTIFY_BUS_ADD:
|
||||
mctp_i3c_bus_add_new((struct i3c_bus *)data, NULL);
|
||||
break;
|
||||
case I3C_NOTIFY_BUS_REMOVE:
|
||||
mctp_i3c_notify_bus_remove((struct i3c_bus *)data);
|
||||
break;
|
||||
}
|
||||
return NOTIFY_DONE;
|
||||
}
|
||||
|
||||
static struct notifier_block mctp_i3c_notifier = {
|
||||
.notifier_call = mctp_i3c_notifier_call,
|
||||
};
|
||||
|
||||
static const struct i3c_device_id mctp_i3c_ids[] = {
|
||||
I3C_CLASS(I3C_DCR_MCTP, NULL),
|
||||
{ 0 },
|
||||
};
|
||||
|
||||
static struct i3c_driver mctp_i3c_driver = {
|
||||
.driver = {
|
||||
.name = "mctp-i3c",
|
||||
},
|
||||
.probe = mctp_i3c_probe,
|
||||
.remove = mctp_i3c_remove,
|
||||
.id_table = mctp_i3c_ids,
|
||||
};
|
||||
|
||||
static __init int mctp_i3c_mod_init(void)
|
||||
{
|
||||
int rc;
|
||||
|
||||
rc = i3c_register_notifier(&mctp_i3c_notifier);
|
||||
if (rc < 0) {
|
||||
i3c_driver_unregister(&mctp_i3c_driver);
|
||||
return rc;
|
||||
}
|
||||
|
||||
i3c_for_each_bus_locked(mctp_i3c_bus_add_new, NULL);
|
||||
|
||||
rc = i3c_driver_register(&mctp_i3c_driver);
|
||||
if (rc < 0)
|
||||
return rc;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static __exit void mctp_i3c_mod_exit(void)
|
||||
{
|
||||
int rc;
|
||||
|
||||
i3c_driver_unregister(&mctp_i3c_driver);
|
||||
|
||||
rc = i3c_unregister_notifier(&mctp_i3c_notifier);
|
||||
if (rc < 0)
|
||||
pr_warn("MCTP I3C could not unregister notifier, %d\n", rc);
|
||||
|
||||
mctp_i3c_bus_remove_all();
|
||||
}
|
||||
|
||||
module_init(mctp_i3c_mod_init);
|
||||
module_exit(mctp_i3c_mod_exit);
|
||||
|
||||
MODULE_DEVICE_TABLE(i3c, mctp_i3c_ids);
|
||||
MODULE_DESCRIPTION("MCTP I3C device");
|
||||
MODULE_LICENSE("GPL");
|
||||
MODULE_AUTHOR("Matt Johnston <matt@codeconstruct.com.au>");
|
||||
Loading…
Reference in a new issue