6.18-stable review patch. If anyone has any objections, please let me know.
------------------
From: Johan Hovold johan@kernel.org
[ Upstream commit 495df2da6944477d282d5cc0c13174d06e25b310 ]
The MOST I2C driver has been completely broken for five years without anyone noticing so remove the driver from staging.
Specifically, commit 723de0f9171e ("staging: most: remove device from interface structure") started requiring drivers to set the interface device pointer before registration, but the I2C driver was never updated which results in a NULL pointer dereference if anyone ever tries to probe it.
Fixes: 723de0f9171e ("staging: most: remove device from interface structure") Cc: Christian Gromm christian.gromm@microchip.com Signed-off-by: Johan Hovold johan@kernel.org Link: https://patch.msgid.link/20251029093442.29256-1-johan@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/staging/most/Kconfig | 2 - drivers/staging/most/Makefile | 1 - drivers/staging/most/i2c/Kconfig | 13 -- drivers/staging/most/i2c/Makefile | 4 - drivers/staging/most/i2c/i2c.c | 374 ------------------------------ 5 files changed, 394 deletions(-) delete mode 100644 drivers/staging/most/i2c/Kconfig delete mode 100644 drivers/staging/most/i2c/Makefile delete mode 100644 drivers/staging/most/i2c/i2c.c
diff --git a/drivers/staging/most/Kconfig b/drivers/staging/most/Kconfig index 6f420cbcdcfff..e89658df6f124 100644 --- a/drivers/staging/most/Kconfig +++ b/drivers/staging/most/Kconfig @@ -24,6 +24,4 @@ source "drivers/staging/most/video/Kconfig"
source "drivers/staging/most/dim2/Kconfig"
-source "drivers/staging/most/i2c/Kconfig" - endif diff --git a/drivers/staging/most/Makefile b/drivers/staging/most/Makefile index 8b3fc5a7af514..e45084df7803a 100644 --- a/drivers/staging/most/Makefile +++ b/drivers/staging/most/Makefile @@ -3,4 +3,3 @@ obj-$(CONFIG_MOST_NET) += net/ obj-$(CONFIG_MOST_VIDEO) += video/ obj-$(CONFIG_MOST_DIM2) += dim2/ -obj-$(CONFIG_MOST_I2C) += i2c/ diff --git a/drivers/staging/most/i2c/Kconfig b/drivers/staging/most/i2c/Kconfig deleted file mode 100644 index ff64283cbad18..0000000000000 --- a/drivers/staging/most/i2c/Kconfig +++ /dev/null @@ -1,13 +0,0 @@ -# SPDX-License-Identifier: GPL-2.0 -# -# MOST I2C configuration -# - -config MOST_I2C - tristate "I2C" - depends on I2C - help - Say Y here if you want to connect via I2C to network transceiver. - - To compile this driver as a module, choose M here: the - module will be called most_i2c. diff --git a/drivers/staging/most/i2c/Makefile b/drivers/staging/most/i2c/Makefile deleted file mode 100644 index 71099dd0f85b9..0000000000000 --- a/drivers/staging/most/i2c/Makefile +++ /dev/null @@ -1,4 +0,0 @@ -# SPDX-License-Identifier: GPL-2.0 -obj-$(CONFIG_MOST_I2C) += most_i2c.o - -most_i2c-objs := i2c.o diff --git a/drivers/staging/most/i2c/i2c.c b/drivers/staging/most/i2c/i2c.c deleted file mode 100644 index 184b2dd11fc34..0000000000000 --- a/drivers/staging/most/i2c/i2c.c +++ /dev/null @@ -1,374 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * i2c.c - Hardware Dependent Module for I2C Interface - * - * Copyright (C) 2013-2015, Microchip Technology Germany II GmbH & Co. KG - */ - -#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt - -#include <linux/init.h> -#include <linux/module.h> -#include <linux/slab.h> -#include <linux/i2c.h> -#include <linux/interrupt.h> -#include <linux/err.h> -#include <linux/most.h> - -enum { CH_RX, CH_TX, NUM_CHANNELS }; - -#define MAX_BUFFERS_CONTROL 32 -#define MAX_BUF_SIZE_CONTROL 256 - -/** - * list_first_mbo - get the first mbo from a list - * @ptr: the list head to take the mbo from. - */ -#define list_first_mbo(ptr) \ - list_first_entry(ptr, struct mbo, list) - -static unsigned int polling_rate; -module_param(polling_rate, uint, 0644); -MODULE_PARM_DESC(polling_rate, "Polling rate [Hz]. Default = 0 (use IRQ)"); - -struct hdm_i2c { - struct most_interface most_iface; - struct most_channel_capability capabilities[NUM_CHANNELS]; - struct i2c_client *client; - struct rx { - struct delayed_work dwork; - struct list_head list; - bool int_disabled; - unsigned int delay; - } rx; - char name[64]; -}; - -static inline struct hdm_i2c *to_hdm(struct most_interface *iface) -{ - return container_of(iface, struct hdm_i2c, most_iface); -} - -static irqreturn_t most_irq_handler(int, void *); -static void pending_rx_work(struct work_struct *); - -/** - * configure_channel - called from MOST core to configure a channel - * @most_iface: interface the channel belongs to - * @ch_idx: channel to be configured - * @channel_config: structure that holds the configuration information - * - * Return 0 on success, negative on failure. - * - * Receives configuration information from MOST core and initialize the - * corresponding channel. - */ -static int configure_channel(struct most_interface *most_iface, - int ch_idx, - struct most_channel_config *channel_config) -{ - int ret; - struct hdm_i2c *dev = to_hdm(most_iface); - unsigned int delay, pr; - - BUG_ON(ch_idx < 0 || ch_idx >= NUM_CHANNELS); - - if (channel_config->data_type != MOST_CH_CONTROL) { - pr_err("bad data type for channel %d\n", ch_idx); - return -EPERM; - } - - if (channel_config->direction != dev->capabilities[ch_idx].direction) { - pr_err("bad direction for channel %d\n", ch_idx); - return -EPERM; - } - - if (channel_config->direction == MOST_CH_RX) { - if (!polling_rate) { - if (dev->client->irq <= 0) { - pr_err("bad irq: %d\n", dev->client->irq); - return -ENOENT; - } - dev->rx.int_disabled = false; - ret = request_irq(dev->client->irq, most_irq_handler, 0, - dev->client->name, dev); - if (ret) { - pr_err("request_irq(%d) failed: %d\n", - dev->client->irq, ret); - return ret; - } - } else { - delay = msecs_to_jiffies(MSEC_PER_SEC / polling_rate); - dev->rx.delay = delay ? delay : 1; - pr = MSEC_PER_SEC / jiffies_to_msecs(dev->rx.delay); - pr_info("polling rate is %u Hz\n", pr); - } - } - - return 0; -} - -/** - * enqueue - called from MOST core to enqueue a buffer for data transfer - * @most_iface: intended interface - * @ch_idx: ID of the channel the buffer is intended for - * @mbo: pointer to the buffer object - * - * Return 0 on success, negative on failure. - * - * Transmit the data over I2C if it is a "write" request or push the buffer into - * list if it is an "read" request - */ -static int enqueue(struct most_interface *most_iface, - int ch_idx, struct mbo *mbo) -{ - struct hdm_i2c *dev = to_hdm(most_iface); - int ret; - - BUG_ON(ch_idx < 0 || ch_idx >= NUM_CHANNELS); - - if (ch_idx == CH_RX) { - /* RX */ - if (!polling_rate) - disable_irq(dev->client->irq); - cancel_delayed_work_sync(&dev->rx.dwork); - list_add_tail(&mbo->list, &dev->rx.list); - if (dev->rx.int_disabled || polling_rate) - pending_rx_work(&dev->rx.dwork.work); - if (!polling_rate) - enable_irq(dev->client->irq); - } else { - /* TX */ - ret = i2c_master_send(dev->client, mbo->virt_address, - mbo->buffer_length); - if (ret <= 0) { - mbo->processed_length = 0; - mbo->status = MBO_E_INVAL; - } else { - mbo->processed_length = mbo->buffer_length; - mbo->status = MBO_SUCCESS; - } - mbo->complete(mbo); - } - - return 0; -} - -/** - * poison_channel - called from MOST core to poison buffers of a channel - * @most_iface: pointer to the interface the channel to be poisoned belongs to - * @ch_idx: corresponding channel ID - * - * Return 0 on success, negative on failure. - * - * If channel direction is RX, complete the buffers in list with - * status MBO_E_CLOSE - */ -static int poison_channel(struct most_interface *most_iface, - int ch_idx) -{ - struct hdm_i2c *dev = to_hdm(most_iface); - struct mbo *mbo; - - BUG_ON(ch_idx < 0 || ch_idx >= NUM_CHANNELS); - - if (ch_idx == CH_RX) { - if (!polling_rate) - free_irq(dev->client->irq, dev); - cancel_delayed_work_sync(&dev->rx.dwork); - - while (!list_empty(&dev->rx.list)) { - mbo = list_first_mbo(&dev->rx.list); - list_del(&mbo->list); - - mbo->processed_length = 0; - mbo->status = MBO_E_CLOSE; - mbo->complete(mbo); - } - } - - return 0; -} - -static void do_rx_work(struct hdm_i2c *dev) -{ - struct mbo *mbo; - unsigned char msg[MAX_BUF_SIZE_CONTROL]; - int ret; - u16 pml, data_size; - - /* Read PML (2 bytes) */ - ret = i2c_master_recv(dev->client, msg, 2); - if (ret <= 0) { - pr_err("Failed to receive PML\n"); - return; - } - - pml = (msg[0] << 8) | msg[1]; - if (!pml) - return; - - data_size = pml + 2; - - /* Read the whole message, including PML */ - ret = i2c_master_recv(dev->client, msg, data_size); - if (ret <= 0) { - pr_err("Failed to receive a Port Message\n"); - return; - } - - mbo = list_first_mbo(&dev->rx.list); - list_del(&mbo->list); - - mbo->processed_length = min(data_size, mbo->buffer_length); - memcpy(mbo->virt_address, msg, mbo->processed_length); - mbo->status = MBO_SUCCESS; - mbo->complete(mbo); -} - -/** - * pending_rx_work - Read pending messages through I2C - * @work: definition of this work item - * - * Invoked by the Interrupt Service Routine, most_irq_handler() - */ -static void pending_rx_work(struct work_struct *work) -{ - struct hdm_i2c *dev = container_of(work, struct hdm_i2c, rx.dwork.work); - - if (list_empty(&dev->rx.list)) - return; - - do_rx_work(dev); - - if (polling_rate) { - schedule_delayed_work(&dev->rx.dwork, dev->rx.delay); - } else { - dev->rx.int_disabled = false; - enable_irq(dev->client->irq); - } -} - -/* - * most_irq_handler - Interrupt Service Routine - * @irq: irq number - * @_dev: private data - * - * Schedules a delayed work - * - * By default the interrupt line behavior is Active Low. Once an interrupt is - * generated by the device, until driver clears the interrupt (by reading - * the PMP message), device keeps the interrupt line in low state. Since i2c - * read is done in work queue, the interrupt line must be disabled temporarily - * to avoid ISR being called repeatedly. Re-enable the interrupt in workqueue, - * after reading the message. - * - * Note: If we use the interrupt line in Falling edge mode, there is a - * possibility to miss interrupts when ISR is getting executed. - * - */ -static irqreturn_t most_irq_handler(int irq, void *_dev) -{ - struct hdm_i2c *dev = _dev; - - disable_irq_nosync(irq); - dev->rx.int_disabled = true; - schedule_delayed_work(&dev->rx.dwork, 0); - - return IRQ_HANDLED; -} - -/* - * i2c_probe - i2c probe handler - * @client: i2c client device structure - * @id: i2c client device id - * - * Return 0 on success, negative on failure. - * - * Register the i2c client device as a MOST interface - */ -static int i2c_probe(struct i2c_client *client) -{ - struct hdm_i2c *dev; - int ret, i; - - dev = kzalloc(sizeof(*dev), GFP_KERNEL); - if (!dev) - return -ENOMEM; - - /* ID format: i2c-<bus>-<address> */ - snprintf(dev->name, sizeof(dev->name), "i2c-%d-%04x", - client->adapter->nr, client->addr); - - for (i = 0; i < NUM_CHANNELS; i++) { - dev->capabilities[i].data_type = MOST_CH_CONTROL; - dev->capabilities[i].num_buffers_packet = MAX_BUFFERS_CONTROL; - dev->capabilities[i].buffer_size_packet = MAX_BUF_SIZE_CONTROL; - } - dev->capabilities[CH_RX].direction = MOST_CH_RX; - dev->capabilities[CH_RX].name_suffix = "rx"; - dev->capabilities[CH_TX].direction = MOST_CH_TX; - dev->capabilities[CH_TX].name_suffix = "tx"; - - dev->most_iface.interface = ITYPE_I2C; - dev->most_iface.description = dev->name; - dev->most_iface.num_channels = NUM_CHANNELS; - dev->most_iface.channel_vector = dev->capabilities; - dev->most_iface.configure = configure_channel; - dev->most_iface.enqueue = enqueue; - dev->most_iface.poison_channel = poison_channel; - - INIT_LIST_HEAD(&dev->rx.list); - - INIT_DELAYED_WORK(&dev->rx.dwork, pending_rx_work); - - dev->client = client; - i2c_set_clientdata(client, dev); - - ret = most_register_interface(&dev->most_iface); - if (ret) { - pr_err("Failed to register i2c as a MOST interface\n"); - kfree(dev); - return ret; - } - - return 0; -} - -/* - * i2c_remove - i2c remove handler - * @client: i2c client device structure - * - * Return 0 on success. - * - * Unregister the i2c client device as a MOST interface - */ -static void i2c_remove(struct i2c_client *client) -{ - struct hdm_i2c *dev = i2c_get_clientdata(client); - - most_deregister_interface(&dev->most_iface); - kfree(dev); -} - -static const struct i2c_device_id i2c_id[] = { - { "most_i2c" }, - { } /* Terminating entry */ -}; - -MODULE_DEVICE_TABLE(i2c, i2c_id); - -static struct i2c_driver i2c_driver = { - .driver = { - .name = "hdm_i2c", - }, - .probe = i2c_probe, - .remove = i2c_remove, - .id_table = i2c_id, -}; - -module_i2c_driver(i2c_driver); - -MODULE_AUTHOR("Andrey Shvetsov andrey.shvetsov@k2l.de"); -MODULE_DESCRIPTION("I2C Hardware Dependent Module"); -MODULE_LICENSE("GPL");