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Message-ID: <1594007ca2695ea8140fa9606ba7f34a7e174408.camel@linux.intel.com>
Subject: Re: [PATCH v4] HID: intel-ish-hid: ISH firmware loader client driver
From:   Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
To:     Nick Crews <ncrews@chromium.org>,
        Rushikesh S Kadam <rushikesh.s.kadam@intel.com>
Cc:     benjamin.tissoires@redhat.com, jikos@kernel.org,
        jettrink@chromium.org, Gwendal Grignou <gwendal@google.com>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        linux-input@vger.kernel.org
Date:   Mon, 01 Apr 2019 17:37:15 -0700
In-Reply-To: <CAHX4x87a4ZScNybtmBmQJUO=JCxPsdFL-QKeX6pviPGh9jD8uA@mail.gmail.com>
References: <1553945015-10919-1-git-send-email-rushikesh.s.kadam@intel.com>
         <CAHX4x87a4ZScNybtmBmQJUO=JCxPsdFL-QKeX6pviPGh9jD8uA@mail.gmail.com>
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On Mon, 2019-04-01 at 17:13 -0600, Nick Crews wrote:
> Looks good to me! Thanks for the work!
> 
So I assume, Rushikesh can add your Reviewed-by.

Thanks,
Srinivas


> On Sat, Mar 30, 2019 at 5:23 AM Rushikesh S Kadam
> <rushikesh.s.kadam@intel.com> wrote:
> > 
> > This driver adds support for loading Intel Integrated
> > Sensor Hub (ISH) firmware from host file system to ISH
> > SRAM and start execution.
> > 
> > At power-on, the ISH subsystem shall boot to an interim
> > Shim loader-firmware, which shall expose an ISHTP loader
> > device.
> > 
> > The driver implements an ISHTP client that communicates
> > with the Shim ISHTP loader device over the intel-ish-hid
> > stack, to download the main ISH firmware.
> > 
> > Signed-off-by: Rushikesh S Kadam <rushikesh.s.kadam@intel.com>
> > ---
> > The patches are baselined to hid git tree, branch for-5.2/ish
> > 
https://git.kernel.org/pub/scm/linux/kernel/git/hid/hid.git/log/?h=for-5.2/ish
> > 
> > v4
> >  - Changed process_recv() to wake the caller in case of
> >    error as well. Earlier caller would wait until timeout on
> >    an error.
> >  - Change sequence of few checks in process_recv().
> > 
> > v3
> >  - Moved a couple of sanity checks from loader_cl_send() to
> >    process_recv().
> >  - Several minor changes to address review comments.
> > 
> > v2
> >  - Change loader_cl_send() so that the calling function
> >    shall allocate and pass the buffer to be used for
> >    receiving firwmare response data. Corresponding changes
> >    in calling function and process_recv().
> >  - Introduced struct response_info to encapsulate and pass
> >    data between from the process_recv() callback to
> >    calling function loader_cl_send().
> >  - Keep count of host firmware load retries, and fail after
> >    3 unsuccessful attempts.
> >  - Dropped report_bad_packets() function previously used for
> >    keeping count of bad packets.
> >  - Inlined loader_ish_hw_reset()'s functionality
> > 
> > v1
> >  - Initial version.
> > 
> >  drivers/hid/Makefile                        |    1 +
> >  drivers/hid/intel-ish-hid/Kconfig           |   15 +
> >  drivers/hid/intel-ish-hid/Makefile          |    3 +
> >  drivers/hid/intel-ish-hid/ishtp-fw-loader.c | 1085
> > +++++++++++++++++++++++++++
> >  4 files changed, 1104 insertions(+)
> >  create mode 100644 drivers/hid/intel-ish-hid/ishtp-fw-loader.c
> > 
> > diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
> > index 170163b..d8d393e 100644
> > --- a/drivers/hid/Makefile
> > +++ b/drivers/hid/Makefile
> > @@ -134,3 +134,4 @@ obj-$(CONFIG_USB_KBD)               += usbhid/
> >  obj-$(CONFIG_I2C_HID)          += i2c-hid/
> > 
> >  obj-$(CONFIG_INTEL_ISH_HID)    += intel-ish-hid/
> > +obj-$(INTEL_ISH_FIRMWARE_DOWNLOADER)   += intel-ish-hid/
> > diff --git a/drivers/hid/intel-ish-hid/Kconfig b/drivers/hid/intel-
> > ish-hid/Kconfig
> > index 519e4c8..786adbc 100644
> > --- a/drivers/hid/intel-ish-hid/Kconfig
> > +++ b/drivers/hid/intel-ish-hid/Kconfig
> > @@ -14,4 +14,19 @@ config INTEL_ISH_HID
> >           Broxton and Kaby Lake.
> > 
> >           Say Y here if you want to support Intel ISH. If unsure,
> > say N.
> > +
> > +config INTEL_ISH_FIRMWARE_DOWNLOADER
> > +       tristate "Host Firmware Load feature for Intel ISH"
> > +       depends on INTEL_ISH_HID
> > +       depends on X86
> > +       help
> > +         The Integrated Sensor Hub (ISH) enables the kernel to
> > offload
> > +         sensor polling and algorithm processing to a dedicated
> > low power
> > +         processor in the chipset.
> > +
> > +         The Host Firmware Load feature adds support to load the
> > ISH
> > +         firmware from host file system at boot.
> > +
> > +         Say M here if you want to support Host Firmware Loading
> > feature
> > +         for Intel ISH. If unsure, say N.
> >  endmenu
> > diff --git a/drivers/hid/intel-ish-hid/Makefile
> > b/drivers/hid/intel-ish-hid/Makefile
> > index 825b70a..2de97e4 100644
> > --- a/drivers/hid/intel-ish-hid/Makefile
> > +++ b/drivers/hid/intel-ish-hid/Makefile
> > @@ -20,4 +20,7 @@ obj-$(CONFIG_INTEL_ISH_HID) += intel-ishtp-hid.o
> >  intel-ishtp-hid-objs := ishtp-hid.o
> >  intel-ishtp-hid-objs += ishtp-hid-client.o
> > 
> > +obj-$(CONFIG_INTEL_ISH_FIRMWARE_DOWNLOADER) += intel-ishtp-
> > loader.o
> > +intel-ishtp-loader-objs += ishtp-fw-loader.o
> > +
> >  ccflags-y += -Idrivers/hid/intel-ish-hid/ishtp
> > diff --git a/drivers/hid/intel-ish-hid/ishtp-fw-loader.c
> > b/drivers/hid/intel-ish-hid/ishtp-fw-loader.c
> > new file mode 100644
> > index 0000000..e770e22
> > --- /dev/null
> > +++ b/drivers/hid/intel-ish-hid/ishtp-fw-loader.c
> > @@ -0,0 +1,1085 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * ISH-TP client driver for ISH firmware loading
> > + *
> > + * Copyright (c) 2019, Intel Corporation.
> > + */
> > +
> > +#include <linux/firmware.h>
> > +#include <linux/module.h>
> > +#include <linux/pci.h>
> > +#include <linux/intel-ish-client-if.h>
> > +#include <linux/property.h>
> > +#include <asm/cacheflush.h>
> > +
> > +/* Number of times we attempt to load the firmware before giving
> > up */
> > +#define MAX_LOAD_ATTEMPTS                      3
> > +
> > +/* ISH TX/RX ring buffer pool size */
> > +#define LOADER_CL_RX_RING_SIZE                 1
> > +#define LOADER_CL_TX_RING_SIZE                 1
> > +
> > +/*
> > + * ISH Shim firmware loader reserves 4 Kb buffer in SRAM. The
> > buffer is
> > + * used to temporarily hold the data transferred from host to Shim
> > + * firmware loader. Reason for the odd size of 3968 bytes? Each
> > IPC
> > + * transfer is 128 bytes (= 4 bytes header + 124 bytes payload).
> > So the
> > + * 4 Kb buffer can hold maximum of 32 IPC transfers, which means
> > we can
> > + * have a max payload of 3968 bytes (= 32 x 124 payload).
> > + */
> > +#define LOADER_SHIM_IPC_BUF_SIZE               3968
> > +
> > +/**
> > + * enum ish_loader_commands -  ISH loader host commands.
> > + * LOADER_CMD_XFER_QUERY       Query the Shim firmware loader for
> > + *                             capabilities
> > + * LOADER_CMD_XFER_FRAGMENT    Transfer one firmware image
> > fragment at a
> > + *                             time. The command may be executed
> > + *                             multiple times until the entire
> > firmware
> > + *                             image is downloaded to SRAM.
> > + * LOADER_CMD_START            Start executing the main firmware.
> > + */
> > +enum ish_loader_commands {
> > +       LOADER_CMD_XFER_QUERY = 0,
> > +       LOADER_CMD_XFER_FRAGMENT,
> > +       LOADER_CMD_START,
> > +};
> > +
> > +/* Command bit mask */
> > +#define        CMD_MASK                                GENMASK(6,
> > 0)
> > +#define        IS_RESPONSE                             BIT(7)
> > +
> > +/*
> > + * ISH firmware max delay for one transmit failure is 1 Hz,
> > + * and firmware will retry 2 times, so 3 Hz is used for timeout.
> > + */
> > +#define ISHTP_SEND_TIMEOUT                     (3 * HZ)
> > +
> > +/*
> > + * Loader transfer modes:
> > + *
> > + * LOADER_XFER_MODE_ISHTP mode uses the existing ISH-TP mechanism
> > to
> > + * transfer data. This may use IPC or DMA if supported in
> > firmware.
> > + * The buffer size is limited to 4 Kb by the IPC/ISH-TP protocol
> > for
> > + * both IPC & DMA (legacy).
> > + *
> > + * LOADER_XFER_MODE_DIRECT_DMA - firmware loading is a bit
> > different
> > + * from the sensor data streaming. Here we download a large (300+
> > Kb)
> > + * image directly to ISH SRAM memory. There is limited benefit of
> > + * DMA'ing 300 Kb image in 4 Kb chucks limit. Hence, we introduce
> > + * this "direct dma" mode, where we do not use ISH-TP for DMA, but
> > + * instead manage the DMA directly in kernel driver and Shim
> > firmware
> > + * loader (allocate buffer, break in chucks and transfer). This
> > allows
> > + * to overcome 4 Kb limit, and optimize the data flow path in
> > firmware.
> > + */
> > +#define LOADER_XFER_MODE_DIRECT_DMA            BIT(0)
> > +#define LOADER_XFER_MODE_ISHTP                 BIT(1)
> > +
> > +/* ISH Transport Loader client unique GUID */
> > +static const guid_t loader_ishtp_guid =
> > +       GUID_INIT(0xc804d06a, 0x55bd, 0x4ea7,
> > +                 0xad, 0xed, 0x1e, 0x31, 0x22, 0x8c, 0x76, 0xdc);
> > +
> > +#define FILENAME_SIZE                          256
> > +
> > +/*
> > + * The firmware loading latency will be minimum if we can DMA the
> > + * entire ISH firmware image in one go. This requires that we
> > allocate
> > + * a large DMA buffer in kernel, which could be problematic on
> > some
> > + * platforms. So here we limit the DMA buffer size via a
> > module_param.
> > + * We default to 4 pages, but a customer can set it to higher
> > limit if
> > + * deemed appropriate for his platform.
> > + */
> > +static int dma_buf_size_limit = 4 * PAGE_SIZE;
> > +
> > +/**
> > + * struct loader_msg_hdr - Header for ISH Loader commands.
> > + * @command:           LOADER_CMD* commands. Bit 7 is the
> > response.
> > + * @status:            Command response status. Non 0, is error
> > + *                     condition.
> > + *
> > + * This structure is used as header for every command/data
> > sent/received
> > + * between Host driver and ISH Shim firmware loader.
> > + */
> > +struct loader_msg_hdr {
> > +       u8 command;
> > +       u8 reserved[2];
> > +       u8 status;
> > +} __packed;
> > +
> > +struct loader_xfer_query {
> > +       struct loader_msg_hdr hdr;
> > +       u32 image_size;
> > +} __packed;
> > +
> > +struct ish_fw_version {
> > +       u16 major;
> > +       u16 minor;
> > +       u16 hotfix;
> > +       u16 build;
> > +} __packed;
> > +
> > +union loader_version {
> > +       u32 value;
> > +       struct {
> > +               u8 major;
> > +               u8 minor;
> > +               u8 hotfix;
> > +               u8 build;
> > +       };
> > +} __packed;
> > +
> > +struct loader_capability {
> > +       u32 max_fw_image_size;
> > +       u32 xfer_mode;
> > +       u32 max_dma_buf_size; /* only for dma mode, multiples of
> > cacheline */
> > +} __packed;
> > +
> > +struct shim_fw_info {
> > +       struct ish_fw_version ish_fw_version;
> > +       u32 protocol_version;
> > +       union loader_version ldr_version;
> > +       struct loader_capability ldr_capability;
> > +} __packed;
> > +
> > +struct loader_xfer_query_response {
> > +       struct loader_msg_hdr hdr;
> > +       struct shim_fw_info fw_info;
> > +} __packed;
> > +
> > +struct loader_xfer_fragment {
> > +       struct loader_msg_hdr hdr;
> > +       u32 xfer_mode;
> > +       u32 offset;
> > +       u32 size;
> > +       u32 is_last;
> > +} __packed;
> > +
> > +struct loader_xfer_ipc_fragment {
> > +       struct loader_xfer_fragment fragment;
> > +       u8 data[] ____cacheline_aligned; /* variable length payload
> > here */
> > +} __packed;
> > +
> > +struct loader_xfer_dma_fragment {
> > +       struct loader_xfer_fragment fragment;
> > +       u64 ddr_phys_addr;
> > +} __packed;
> > +
> > +struct loader_start {
> > +       struct loader_msg_hdr hdr;
> > +} __packed;
> > +
> > +/**
> > + * struct response_info - Encapsulate firmware response related
> > + *                     information for passing between function
> > + *                     loader_cl_send() and process_recv()
> > callback.
> > + * @data               Copy the data received from firmware here.
> > + * @max_size           Max size allocated for the @data buffer. If
> > the
> > + *                     received data exceeds this value, we log an
> > + *                     error.
> > + * @size               Actual size of data received from firmware.
> > + * @error              Returns 0 for success, negative error code
> > for a
> > + *                     failure in function process_recv().
> > + * @received           Set to true on receiving a valid firmware
> > + *                     response to host command
> > + * @wait_queue         Wait queue for Host firmware loading where
> > the
> > + *                     client sends message to ISH firmware and
> > waits
> > + *                     for response
> > + */
> > +struct response_info {
> > +       void *data;
> > +       size_t max_size;
> > +       size_t size;
> > +       int error;
> > +       bool received;
> > +       wait_queue_head_t wait_queue;
> > +};
> > +
> > +/**
> > + * struct ishtp_cl_data - Encapsulate per ISH-TP Client Data.
> > + * @work_ishtp_reset:  Work queue for reset handling.
> > + * @work_fw_load:      Work queue for host firmware loading.
> > + * @flag_retry         Flag for indicating host firmware loading
> > should
> > + *                     be retried.
> > + * @retry_count                Count the number of retries.
> > + *
> > + * This structure is used to store data per client.
> > + */
> > +struct ishtp_cl_data {
> > +       struct ishtp_cl *loader_ishtp_cl;
> > +       struct ishtp_cl_device *cl_device;
> > +
> > +       /*
> > +        * Used for passing firmware response information between
> > +        * loader_cl_send() and process_recv() callback.
> > +        */
> > +       struct response_info response;
> > +
> > +       struct work_struct work_ishtp_reset;
> > +       struct work_struct work_fw_load;
> > +
> > +       /*
> > +        * In certain failure scenrios, it makes sense to reset the
> > ISH
> > +        * subsystem and retry Host firmware loading (e.g. bad
> > message
> > +        * packet, ENOMEM, etc.). On the other hand, failures due
> > to
> > +        * protocol mismatch, etc., are not recoverable. We do not
> > +        * retry them.
> > +        *
> > +        * If set, the flag indicates that we should re-try the
> > +        * particular failure.
> > +        */
> > +       bool flag_retry;
> > +       int retry_count;
> > +};
> > +
> > +#define IPC_FRAGMENT_DATA_PREAMBLE                             \
> > +       offsetof(struct loader_xfer_ipc_fragment, data)
> > +
> > +#define cl_data_to_dev(client_data) ishtp_device((client_data)-
> > >cl_device)
> > +
> > +/**
> > + * get_firmware_variant() - Gets the filename of firmware image to
> > be
> > + *                     loaded based on platform variant.
> > + * @client_data                Client data instance.
> > + * @filename           Returns firmware filename.
> > + *
> > + * Queries the firmware-name device property string.
> > + *
> > + * Return: 0 for success, negative error code for failure.
> > + */
> > +static int get_firmware_variant(struct ishtp_cl_data *client_data,
> > +                               char *filename)
> > +{
> > +       int rv;
> > +       const char *val;
> > +       struct device *devc = ishtp_get_pci_device(client_data-
> > >cl_device);
> > +
> > +       rv = device_property_read_string(devc, "firmware-name",
> > &val);
> > +       if (rv < 0) {
> > +               dev_err(devc,
> > +                       "Error: ISH firmware-name device property
> > required\n");
> > +               return rv;
> > +       }
> > +       return snprintf(filename, FILENAME_SIZE, "intel/%s", val);
> > +}
> > +
> > +/**
> > + * loader_cl_send()    Send message from host to firmware
> > + * @client_data:       Client data instance
> > + * @out_msg            Message buffer to be sent to firmware
> > + * @out_size           Size of out going message
> > + * @in_msg             Message buffer where the incoming data
> > copied.
> > + *                     This buffer is allocated by calling
> > + * @in_size            Max size of incoming message
> > + *
> > + * Return: Number of bytes copied in the in_msg on success,
> > negative
> > + * error code on failure.
> > + */
> > +static int loader_cl_send(struct ishtp_cl_data *client_data,
> > +                         u8 *out_msg, size_t out_size,
> > +                         u8 *in_msg, size_t in_size)
> > +{
> > +       int rv;
> > +       struct loader_msg_hdr *out_hdr = (struct loader_msg_hdr
> > *)out_msg;
> > +       struct ishtp_cl *loader_ishtp_cl = client_data-
> > >loader_ishtp_cl;
> > +
> > +       dev_dbg(cl_data_to_dev(client_data),
> > +               "%s: command=%02lx is_response=%u status=%02x\n",
> > +               __func__,
> > +               out_hdr->command & CMD_MASK,
> > +               out_hdr->command & IS_RESPONSE ? 1 : 0,
> > +               out_hdr->status);
> > +
> > +       /* Setup in coming buffer & size */
> > +       client_data->response.data = in_msg;
> > +       client_data->response.max_size = in_size;
> > +       client_data->response.error = 0;
> > +       client_data->response.received = false;
> > +
> > +       rv = ishtp_cl_send(loader_ishtp_cl, out_msg, out_size);
> > +       if (rv < 0) {
> > +               dev_err(cl_data_to_dev(client_data),
> > +                       "ishtp_cl_send error %d\n", rv);
> > +               return rv;
> > +       }
> > +
> > +       wait_event_interruptible_timeout(client_data-
> > >response.wait_queue,
> > +                                        client_data-
> > >response.received,
> > +                                        ISHTP_SEND_TIMEOUT);
> > +       if (!client_data->response.received) {
> > +               dev_err(cl_data_to_dev(client_data),
> > +                       "Timed out for response to command=%02lx",
> > +                       out_hdr->command & CMD_MASK);
> > +               return -ETIMEDOUT;
> > +       }
> > +
> > +       if (client_data->response.error < 0)
> > +               return client_data->response.error;
> > +
> > +       return client_data->response.size;
> > +}
> > +
> > +/**
> > + * process_recv() -    Receive and parse incoming packet
> > + * @loader_ishtp_cl:   Client instance to get stats
> > + * @rb_in_proc:                ISH received message buffer
> > + *
> > + * Parse the incoming packet. If it is a response packet then it
> > will
> > + * update received and wake up the caller waiting to for the
> > response.
> > + */
> > +static void process_recv(struct ishtp_cl *loader_ishtp_cl,
> > +                        struct ishtp_cl_rb *rb_in_proc)
> > +{
> > +       struct loader_msg_hdr *hdr;
> > +       size_t data_len = rb_in_proc->buf_idx;
> > +       struct ishtp_cl_data *client_data =
> > +               ishtp_get_client_data(loader_ishtp_cl);
> > +
> > +       /* Sanity check */
> > +       if (!client_data->response.data) {
> > +               dev_err(cl_data_to_dev(client_data),
> > +                       "Receiving buffer is null. Should be
> > allocated by calling function\n");
> > +               client_data->response.error = -EINVAL;
> > +               goto end;
> > +       }
> > +
> > +       if (client_data->response.received) {
> > +               dev_err(cl_data_to_dev(client_data),
> > +                       "Previous firmware message not yet
> > processed\n");
> > +               client_data->response.error = -EINVAL;
> > +               goto end;
> > +       }
> > +       /*
> > +        * All firmware messages have a header. Check buffer size
> > +        * before accessing elements inside.
> > +        */
> > +       if (!rb_in_proc->buffer.data) {
> > +               dev_warn(cl_data_to_dev(client_data),
> > +                        "rb_in_proc->buffer.data returned null");
> > +               client_data->response.error = -EBADMSG;
> > +               goto end;
> > +       }
> > +
> > +       if (data_len < sizeof(struct loader_msg_hdr)) {
> > +               dev_err(cl_data_to_dev(client_data),
> > +                       "data size %zu is less than header %zu\n",
> > +                       data_len, sizeof(struct loader_msg_hdr));
> > +               client_data->response.error = -EMSGSIZE;
> > +               goto end;
> > +       }
> > +
> > +       hdr = (struct loader_msg_hdr *)rb_in_proc->buffer.data;
> > +
> > +       dev_dbg(cl_data_to_dev(client_data),
> > +               "%s: command=%02lx is_response=%u status=%02x\n",
> > +               __func__,
> > +               hdr->command & CMD_MASK,
> > +               hdr->command & IS_RESPONSE ? 1 : 0,
> > +               hdr->status);
> > +
> > +       if (((hdr->command & CMD_MASK) != LOADER_CMD_XFER_QUERY) &&
> > +           ((hdr->command & CMD_MASK) != LOADER_CMD_XFER_FRAGMENT)
> > &&
> > +           ((hdr->command & CMD_MASK) != LOADER_CMD_START)) {
> > +               dev_err(cl_data_to_dev(client_data),
> > +                       "Invalid command=%02lx\n",
> > +                       hdr->command & CMD_MASK);
> > +               client_data->response.error = -EPROTO;
> > +               goto end;
> > +       }
> > +
> > +       if (data_len > client_data->response.max_size) {
> > +               dev_err(cl_data_to_dev(client_data),
> > +                       "Received buffer size %zu is larger than
> > allocated buffer %zu\n",
> > +                       data_len, client_data->response.max_size);
> > +               client_data->response.error = -EMSGSIZE;
> > +               goto end;
> > +       }
> > +
> > +       /* We expect only "response" messages from firmware */
> > +       if (!(hdr->command & IS_RESPONSE)) {
> > +               dev_err(cl_data_to_dev(client_data),
> > +                       "Invalid response to command\n");
> > +               client_data->response.error = -EIO;
> > +               goto end;
> > +       }
> > +
> > +       if (hdr->status) {
> > +               dev_err(cl_data_to_dev(client_data),
> > +                       "Loader returned status %d\n",
> > +                       hdr->status);
> > +               client_data->response.error = -EIO;
> > +               goto end;
> > +       }
> > +
> > +       /* Update the actual received buffer size */
> > +       client_data->response.size = data_len;
> > +
> > +       /*
> > +        * Copy the buffer received in firmware response for the
> > +        * calling thread.
> > +        */
> > +       memcpy(client_data->response.data,
> > +              rb_in_proc->buffer.data, data_len);
> > +
> > +       /* Set flag before waking up the caller */
> > +       client_data->response.received = true;
> > +
> > +end:
> > +       /* Free the buffer */
> > +       ishtp_cl_io_rb_recycle(rb_in_proc);
> > +       rb_in_proc = NULL;
> > +
> > +       /* Wake the calling thread */
> > +       wake_up_interruptible(&client_data->response.wait_queue);
> > +}
> > +
> > +/**
> > + * loader_cl_event_cb() - bus driver callback for incoming message
> > + * @device:            Pointer to the ishtp client device for
> > which this
> > + *                     message is targeted
> > + *
> > + * Remove the packet from the list and process the message by
> > calling
> > + * process_recv
> > + */
> > +static void loader_cl_event_cb(struct ishtp_cl_device *cl_device)
> > +{
> > +       struct ishtp_cl_rb *rb_in_proc;
> > +       struct ishtp_cl *loader_ishtp_cl =
> > ishtp_get_drvdata(cl_device);
> > +
> > +       while ((rb_in_proc = ishtp_cl_rx_get_rb(loader_ishtp_cl))
> > != NULL) {
> > +               /* Process the data packet from firmware */
> > +               process_recv(loader_ishtp_cl, rb_in_proc);
> > +       }
> > +}
> > +
> > +/**
> > + * ish_query_loader_prop() -  Query ISH Shim firmware loader
> > + * @client_data:       Client data instance
> > + * @fw:                        Poiner to firmware data struct in
> > host memory
> > + * @fw_info:           Loader firmware properties
> > + *
> > + * This function queries the ISH Shim firmware loader for
> > capabilities.
> > + *
> > + * Return: 0 for success, negative error code for failure.
> > + */
> > +static int ish_query_loader_prop(struct ishtp_cl_data
> > *client_data,
> > +                                const struct firmware *fw,
> > +                                struct shim_fw_info *fw_info)
> > +{
> > +       int rv;
> > +       struct loader_xfer_query ldr_xfer_query;
> > +       struct loader_xfer_query_response ldr_xfer_query_resp;
> > +
> > +       memset(&ldr_xfer_query, 0, sizeof(ldr_xfer_query));
> > +       ldr_xfer_query.hdr.command = LOADER_CMD_XFER_QUERY;
> > +       ldr_xfer_query.image_size = fw->size;
> > +       rv = loader_cl_send(client_data,
> > +                           (u8 *)&ldr_xfer_query,
> > +                           sizeof(ldr_xfer_query),
> > +                           (u8 *)&ldr_xfer_query_resp,
> > +                           sizeof(ldr_xfer_query_resp));
> > +       if (rv < 0) {
> > +               client_data->flag_retry = true;
> > +               return rv;
> > +       }
> > +
> > +       /* On success, the return value is the received buffer size
> > */
> > +       if (rv != sizeof(struct loader_xfer_query_response)) {
> > +               dev_err(cl_data_to_dev(client_data),
> > +                       "data size %d is not equal to size of
> > loader_xfer_query_response %zu\n",
> > +                       rv, sizeof(struct
> > loader_xfer_query_response));
> > +               client_data->flag_retry = true;
> > +               return -EMSGSIZE;
> > +       }
> > +
> > +       /* Save fw_info for use outside this function */
> > +       *fw_info = ldr_xfer_query_resp.fw_info;
> > +
> > +       /* Loader firmware properties */
> > +       dev_dbg(cl_data_to_dev(client_data),
> > +               "ish_fw_version: major=%d minor=%d hotfix=%d
> > build=%d protocol_version=0x%x loader_version=%d\n",
> > +               fw_info->ish_fw_version.major,
> > +               fw_info->ish_fw_version.minor,
> > +               fw_info->ish_fw_version.hotfix,
> > +               fw_info->ish_fw_version.build,
> > +               fw_info->protocol_version,
> > +               fw_info->ldr_version.value);
> > +
> > +       dev_dbg(cl_data_to_dev(client_data),
> > +               "loader_capability: max_fw_image_size=0x%x
> > xfer_mode=%d max_dma_buf_size=0x%x dma_buf_size_limit=0x%x\n",
> > +               fw_info->ldr_capability.max_fw_image_size,
> > +               fw_info->ldr_capability.xfer_mode,
> > +               fw_info->ldr_capability.max_dma_buf_size,
> > +               dma_buf_size_limit);
> > +
> > +       /* Sanity checks */
> > +       if (fw_info->ldr_capability.max_fw_image_size < fw->size) {
> > +               dev_err(cl_data_to_dev(client_data),
> > +                       "ISH firmware size %zu is greater than Shim
> > firmware loader max supported %d\n",
> > +                       fw->size,
> > +                       fw_info->ldr_capability.max_fw_image_size);
> > +               return -ENOSPC;
> > +       }
> > +
> > +       /* For DMA the buffer size should be multiple of cacheline
> > size */
> > +       if ((fw_info->ldr_capability.xfer_mode &
> > LOADER_XFER_MODE_DIRECT_DMA) &&
> > +           (fw_info->ldr_capability.max_dma_buf_size %
> > L1_CACHE_BYTES)) {
> > +               dev_err(cl_data_to_dev(client_data),
> > +                       "Shim firmware loader buffer size %d should
> > be multipe of cacheline\n",
> > +                       fw_info->ldr_capability.max_dma_buf_size);
> > +               return -EINVAL;
> > +       }
> > +
> > +       return 0;
> > +}
> > +
> > +/**
> > + * ish_fw_xfer_ishtp() Loads ISH firmware using ishtp interface
> > + * @client_data:       Client data instance
> > + * @fw:                        Pointer to firmware data struct in
> > host memory
> > + *
> > + * This function uses ISH-TP to transfer ISH firmware from host to
> > + * ISH SRAM. Lower layers may use IPC or DMA depending on firmware
> > + * support.
> > + *
> > + * Return: 0 for success, negative error code for failure.
> > + */
> > +static int ish_fw_xfer_ishtp(struct ishtp_cl_data *client_data,
> > +                            const struct firmware *fw)
> > +{
> > +       int rv;
> > +       u32 fragment_offset, fragment_size, payload_max_size;
> > +       struct loader_xfer_ipc_fragment *ldr_xfer_ipc_frag;
> > +       struct loader_msg_hdr ldr_xfer_ipc_ack;
> > +
> > +       payload_max_size =
> > +               LOADER_SHIM_IPC_BUF_SIZE -
> > IPC_FRAGMENT_DATA_PREAMBLE;
> > +
> > +       ldr_xfer_ipc_frag = kzalloc(LOADER_SHIM_IPC_BUF_SIZE,
> > GFP_KERNEL);
> > +       if (!ldr_xfer_ipc_frag) {
> > +               client_data->flag_retry = true;
> > +               return -ENOMEM;
> > +       }
> > +
> > +       ldr_xfer_ipc_frag->fragment.hdr.command =
> > LOADER_CMD_XFER_FRAGMENT;
> > +       ldr_xfer_ipc_frag->fragment.xfer_mode =
> > LOADER_XFER_MODE_ISHTP;
> > +
> > +       /* Break the firmware image into fragments and send as ISH-
> > TP payload */
> > +       fragment_offset = 0;
> > +       while (fragment_offset < fw->size) {
> > +               if (fragment_offset + payload_max_size < fw->size)
> > {
> > +                       fragment_size = payload_max_size;
> > +                       ldr_xfer_ipc_frag->fragment.is_last = 0;
> > +               } else {
> > +                       fragment_size = fw->size - fragment_offset;
> > +                       ldr_xfer_ipc_frag->fragment.is_last = 1;
> > +               }
> > +
> > +               ldr_xfer_ipc_frag->fragment.offset =
> > fragment_offset;
> > +               ldr_xfer_ipc_frag->fragment.size = fragment_size;
> > +               memcpy(ldr_xfer_ipc_frag->data,
> > +                      &fw->data[fragment_offset],
> > +                      fragment_size);
> > +
> > +               dev_dbg(cl_data_to_dev(client_data),
> > +                       "xfer_mode=ipc offset=0x%08x size=0x%08x
> > is_last=%d\n",
> > +                       ldr_xfer_ipc_frag->fragment.offset,
> > +                       ldr_xfer_ipc_frag->fragment.size,
> > +                       ldr_xfer_ipc_frag->fragment.is_last);
> > +
> > +               rv = loader_cl_send(client_data,
> > +                                   (u8 *)ldr_xfer_ipc_frag,
> > +                                   IPC_FRAGMENT_DATA_PREAMBLE +
> > fragment_size,
> > +                                   (u8 *)&ldr_xfer_ipc_ack,
> > +                                   sizeof(ldr_xfer_ipc_ack));
> > +               if (rv < 0) {
> > +                       client_data->flag_retry = true;
> > +                       goto end_err_resp_buf_release;
> > +               }
> > +
> > +               fragment_offset += fragment_size;
> > +       }
> > +
> > +       kfree(ldr_xfer_ipc_frag);
> > +       return 0;
> > +
> > +end_err_resp_buf_release:
> > +       /* Free ISH buffer if not done already, in error case */
> > +       kfree(ldr_xfer_ipc_frag);
> > +       return rv;
> > +}
> > +
> > +/**
> > + * ish_fw_xfer_direct_dma() - Loads ISH firmware using direct dma
> > + * @client_data:       Client data instance
> > + * @fw:                        Pointer to firmware data struct in
> > host memory
> > + * @fw_info:           Loader firmware properties
> > + *
> > + * Host firmware load is a unique case where we need to download
> > + * a large firmware image (200+ Kb). This function implements
> > + * direct DMA transfer in kernel and ISH firmware. This allows
> > + * us to overcome the ISH-TP 4 Kb limit, and allows us to DMA
> > + * directly to ISH UMA at location of choice.
> > + * Function depends on corresponding support in ISH firmware.
> > + *
> > + * Return: 0 for success, negative error code for failure.
> > + */
> > +static int ish_fw_xfer_direct_dma(struct ishtp_cl_data
> > *client_data,
> > +                                 const struct firmware *fw,
> > +                                 const struct shim_fw_info
> > fw_info)
> > +{
> > +       int rv;
> > +       void *dma_buf;
> > +       dma_addr_t dma_buf_phy;
> > +       u32 fragment_offset, fragment_size, payload_max_size;
> > +       struct loader_msg_hdr ldr_xfer_dma_frag_ack;
> > +       struct loader_xfer_dma_fragment ldr_xfer_dma_frag;
> > +       struct device *devc = ishtp_get_pci_device(client_data-
> > >cl_device);
> > +       u32 shim_fw_buf_size =
> > +               fw_info.ldr_capability.max_dma_buf_size;
> > +
> > +       /*
> > +        * payload_max_size should be set to minimum of
> > +        *  (1) Size of firmware to be loaded,
> > +        *  (2) Max DMA buffer size supported by Shim firmware,
> > +        *  (3) DMA buffer size limit set by boot_param
> > dma_buf_size_limit.
> > +        */
> > +       payload_max_size = min3(fw->size,
> > +                               (size_t)shim_fw_buf_size,
> > +                               (size_t)dma_buf_size_limit);
> > +
> > +       /*
> > +        * Buffer size should be multiple of cacheline size
> > +        * if it's not, select the previous cacheline boundary.
> > +        */
> > +       payload_max_size &= ~(L1_CACHE_BYTES - 1);
> > +
> > +       dma_buf = kmalloc(payload_max_size, GFP_KERNEL |
> > GFP_DMA32);
> > +       if (!dma_buf) {
> > +               client_data->flag_retry = true;
> > +               return -ENOMEM;
> > +       }
> > +
> > +       dma_buf_phy = dma_map_single(devc, dma_buf,
> > payload_max_size,
> > +                                    DMA_TO_DEVICE);
> > +       if (dma_mapping_error(devc, dma_buf_phy)) {
> > +               dev_err(cl_data_to_dev(client_data), "DMA map
> > failed\n");
> > +               client_data->flag_retry = true;
> > +               rv = -ENOMEM;
> > +               goto end_err_dma_buf_release;
> > +       }
> > +
> > +       ldr_xfer_dma_frag.fragment.hdr.command =
> > LOADER_CMD_XFER_FRAGMENT;
> > +       ldr_xfer_dma_frag.fragment.xfer_mode =
> > LOADER_XFER_MODE_DIRECT_DMA;
> > +       ldr_xfer_dma_frag.ddr_phys_addr = (u64)dma_buf_phy;
> > +
> > +       /* Send the firmware image in chucks of payload_max_size */
> > +       fragment_offset = 0;
> > +       while (fragment_offset < fw->size) {
> > +               if (fragment_offset + payload_max_size < fw->size)
> > {
> > +                       fragment_size = payload_max_size;
> > +                       ldr_xfer_dma_frag.fragment.is_last = 0;
> > +               } else {
> > +                       fragment_size = fw->size - fragment_offset;
> > +                       ldr_xfer_dma_frag.fragment.is_last = 1;
> > +               }
> > +
> > +               ldr_xfer_dma_frag.fragment.offset =
> > fragment_offset;
> > +               ldr_xfer_dma_frag.fragment.size = fragment_size;
> > +               memcpy(dma_buf, &fw->data[fragment_offset],
> > fragment_size);
> > +
> > +               dma_sync_single_for_device(devc, dma_buf_phy,
> > +                                          payload_max_size,
> > +                                          DMA_TO_DEVICE);
> > +
> > +               /*
> > +                * Flush cache here because the
> > dma_sync_single_for_device()
> > +                * does not do for x86.
> > +                */
> > +               clflush_cache_range(dma_buf, payload_max_size);
> > +
> > +               dev_dbg(cl_data_to_dev(client_data),
> > +                       "xfer_mode=dma offset=0x%08x size=0x%x
> > is_last=%d ddr_phys_addr=0x%016llx\n",
> > +                       ldr_xfer_dma_frag.fragment.offset,
> > +                       ldr_xfer_dma_frag.fragment.size,
> > +                       ldr_xfer_dma_frag.fragment.is_last,
> > +                       ldr_xfer_dma_frag.ddr_phys_addr);
> > +
> > +               rv = loader_cl_send(client_data,
> > +                                   (u8 *)&ldr_xfer_dma_frag,
> > +                                   sizeof(ldr_xfer_dma_frag),
> > +                                   (u8 *)&ldr_xfer_dma_frag_ack,
> > +                                   sizeof(ldr_xfer_dma_frag_ack));
> > +               if (rv < 0) {
> > +                       client_data->flag_retry = true;
> > +                       goto end_err_resp_buf_release;
> > +               }
> > +
> > +               fragment_offset += fragment_size;
> > +       }
> > +
> > +       dma_unmap_single(devc, dma_buf_phy, payload_max_size,
> > DMA_TO_DEVICE);
> > +       kfree(dma_buf);
> > +       return 0;
> > +
> > +end_err_resp_buf_release:
> > +       /* Free ISH buffer if not done already, in error case */
> > +       dma_unmap_single(devc, dma_buf_phy, payload_max_size,
> > DMA_TO_DEVICE);
> > +end_err_dma_buf_release:
> > +       kfree(dma_buf);
> > +       return rv;
> > +}
> > +
> > +/**
> > + * ish_fw_start()      Start executing ISH main firmware
> > + * @client_data:       client data instance
> > + *
> > + * This function sends message to Shim firmware loader to start
> > + * the execution of ISH main firmware.
> > + *
> > + * Return: 0 for success, negative error code for failure.
> > + */
> > +static int ish_fw_start(struct ishtp_cl_data *client_data)
> > +{
> > +       struct loader_start ldr_start;
> > +       struct loader_msg_hdr ldr_start_ack;
> > +
> > +       memset(&ldr_start, 0, sizeof(ldr_start));
> > +       ldr_start.hdr.command = LOADER_CMD_START;
> > +       return loader_cl_send(client_data,
> > +                           (u8 *)&ldr_start,
> > +                           sizeof(ldr_start),
> > +                           (u8 *)&ldr_start_ack,
> > +                           sizeof(ldr_start_ack));
> > +}
> > +
> > +/**
> > + * load_fw_from_host() Loads ISH firmware from host
> > + * @client_data:       Client data instance
> > + *
> > + * This function loads the ISH firmware to ISH SRAM and starts
> > execution
> > + *
> > + * Return: 0 for success, negative error code for failure.
> > + */
> > +static int load_fw_from_host(struct ishtp_cl_data *client_data)
> > +{
> > +       int rv;
> > +       u32 xfer_mode;
> > +       char *filename;
> > +       const struct firmware *fw;
> > +       struct shim_fw_info fw_info;
> > +       struct ishtp_cl *loader_ishtp_cl = client_data-
> > >loader_ishtp_cl;
> > +
> > +       client_data->flag_retry = false;
> > +
> > +       filename = kzalloc(FILENAME_SIZE, GFP_KERNEL);
> > +       if (!filename) {
> > +               client_data->flag_retry = true;
> > +               rv = -ENOMEM;
> > +               goto end_error;
> > +       }
> > +
> > +       /* Get filename of the ISH firmware to be loaded */
> > +       rv = get_firmware_variant(client_data, filename);
> > +       if (rv < 0)
> > +               goto end_err_filename_buf_release;
> > +
> > +       rv = request_firmware(&fw, filename,
> > cl_data_to_dev(client_data));
> > +       if (rv < 0)
> > +               goto end_err_filename_buf_release;
> > +
> > +       /* Step 1: Query Shim firmware loader properties */
> > +
> > +       rv = ish_query_loader_prop(client_data, fw, &fw_info);
> > +       if (rv < 0)
> > +               goto end_err_fw_release;
> > +
> > +       /* Step 2: Send the main firmware image to be loaded, to
> > ISH SRAM */
> > +
> > +       xfer_mode = fw_info.ldr_capability.xfer_mode;
> > +       if (xfer_mode & LOADER_XFER_MODE_DIRECT_DMA) {
> > +               rv = ish_fw_xfer_direct_dma(client_data, fw,
> > fw_info);
> > +       } else if (xfer_mode & LOADER_XFER_MODE_ISHTP) {
> > +               rv = ish_fw_xfer_ishtp(client_data, fw);
> > +       } else {
> > +               dev_err(cl_data_to_dev(client_data),
> > +                       "No transfer mode selected in firmware\n");
> > +               rv = -EINVAL;
> > +       }
> > +       if (rv < 0)
> > +               goto end_err_fw_release;
> > +
> > +       /* Step 3: Start ISH main firmware exeuction */
> > +
> > +       rv = ish_fw_start(client_data);
> > +       if (rv < 0)
> > +               goto end_err_fw_release;
> > +
> > +       release_firmware(fw);
> > +       kfree(filename);
> > +       dev_info(cl_data_to_dev(client_data), "ISH firmware %s
> > loaded\n",
> > +                filename);
> > +       return 0;
> > +
> > +end_err_fw_release:
> > +       release_firmware(fw);
> > +end_err_filename_buf_release:
> > +       kfree(filename);
> > +end_error:
> > +       /* Keep a count of retries, and give up after 3 attempts */
> > +       if (client_data->flag_retry &&
> > +           client_data->retry_count++ < MAX_LOAD_ATTEMPTS) {
> > +               dev_warn(cl_data_to_dev(client_data),
> > +                        "ISH host firmware load failed %d.
> > Resetting ISH, and trying again..\n",
> > +                        rv);
> > +               ish_hw_reset(ishtp_get_ishtp_device(loader_ishtp_cl
> > ));
> > +       } else {
> > +               dev_err(cl_data_to_dev(client_data),
> > +                       "ISH host firmware load failed %d\n", rv);
> > +       }
> > +       return rv;
> > +}
> > +
> > +static void load_fw_from_host_handler(struct work_struct *work)
> > +{
> > +       struct ishtp_cl_data *client_data;
> > +
> > +       client_data = container_of(work, struct ishtp_cl_data,
> > +                                  work_fw_load);
> > +       load_fw_from_host(client_data);
> > +}
> > +
> > +/**
> > + * loader_init() -     Init function for ISH-TP client
> > + * @loader_ishtp_cl:   ISH-TP client instance
> > + * @reset:             true if called for init after reset
> > + *
> > + * Return: 0 for success, negative error code for failure
> > + */
> > +static int loader_init(struct ishtp_cl *loader_ishtp_cl, int
> > reset)
> > +{
> > +       int rv;
> > +       struct ishtp_fw_client *fw_client;
> > +       struct ishtp_cl_data *client_data =
> > +               ishtp_get_client_data(loader_ishtp_cl);
> > +
> > +       dev_dbg(cl_data_to_dev(client_data), "reset flag: %d\n",
> > reset);
> > +
> > +       rv = ishtp_cl_link(loader_ishtp_cl);
> > +       if (rv < 0) {
> > +               dev_err(cl_data_to_dev(client_data), "ishtp_cl_link
> > failed\n");
> > +               return rv;
> > +       }
> > +
> > +       /* Connect to firmware client */
> > +       ishtp_set_tx_ring_size(loader_ishtp_cl,
> > LOADER_CL_TX_RING_SIZE);
> > +       ishtp_set_rx_ring_size(loader_ishtp_cl,
> > LOADER_CL_RX_RING_SIZE);
> > +
> > +       fw_client =
> > +               ishtp_fw_cl_get_client(ishtp_get_ishtp_device(loade
> > r_ishtp_cl),
> > +                                      &loader_ishtp_guid);
> > +       if (!fw_client) {
> > +               dev_err(cl_data_to_dev(client_data),
> > +                       "ISH client uuid not found\n");
> > +               rv = -ENOENT;
> > +               goto err_cl_unlink;
> > +       }
> > +
> > +       ishtp_cl_set_fw_client_id(loader_ishtp_cl,
> > +                                 ishtp_get_fw_client_id(fw_client)
> > );
> > +       ishtp_set_connection_state(loader_ishtp_cl,
> > ISHTP_CL_CONNECTING);
> > +
> > +       rv = ishtp_cl_connect(loader_ishtp_cl);
> > +       if (rv < 0) {
> > +               dev_err(cl_data_to_dev(client_data), "Client
> > connect fail\n");
> > +               goto err_cl_unlink;
> > +       }
> > +
> > +       dev_dbg(cl_data_to_dev(client_data), "Client connected\n");
> > +
> > +       ishtp_register_event_cb(client_data->cl_device,
> > loader_cl_event_cb);
> > +
> > +       return 0;
> > +
> > +err_cl_unlink:
> > +       ishtp_cl_unlink(loader_ishtp_cl);
> > +       return rv;
> > +}
> > +
> > +static void loader_deinit(struct ishtp_cl *loader_ishtp_cl)
> > +{
> > +       ishtp_set_connection_state(loader_ishtp_cl,
> > ISHTP_CL_DISCONNECTING);
> > +       ishtp_cl_disconnect(loader_ishtp_cl);
> > +       ishtp_cl_unlink(loader_ishtp_cl);
> > +       ishtp_cl_flush_queues(loader_ishtp_cl);
> > +
> > +       /* Disband and free all Tx and Rx client-level rings */
> > +       ishtp_cl_free(loader_ishtp_cl);
> > +}
> > +
> > +static void reset_handler(struct work_struct *work)
> > +{
> > +       int rv;
> > +       struct ishtp_cl_data *client_data;
> > +       struct ishtp_cl *loader_ishtp_cl;
> > +       struct ishtp_cl_device *cl_device;
> > +
> > +       client_data = container_of(work, struct ishtp_cl_data,
> > +                                  work_ishtp_reset);
> > +
> > +       loader_ishtp_cl = client_data->loader_ishtp_cl;
> > +       cl_device = client_data->cl_device;
> > +
> > +       /* Unlink, flush queues & start again */
> > +       ishtp_cl_unlink(loader_ishtp_cl);
> > +       ishtp_cl_flush_queues(loader_ishtp_cl);
> > +       ishtp_cl_free(loader_ishtp_cl);
> > +
> > +       loader_ishtp_cl = ishtp_cl_allocate(cl_device);
> > +       if (!loader_ishtp_cl)
> > +               return;
> > +
> > +       ishtp_set_drvdata(cl_device, loader_ishtp_cl);
> > +       ishtp_set_client_data(loader_ishtp_cl, client_data);
> > +       client_data->loader_ishtp_cl = loader_ishtp_cl;
> > +       client_data->cl_device = cl_device;
> > +
> > +       rv = loader_init(loader_ishtp_cl, 1);
> > +       if (rv < 0) {
> > +               dev_err(ishtp_device(cl_device), "Reset Failed\n");
> > +               return;
> > +       }
> > +
> > +       /* ISH firmware loading from host */
> > +       load_fw_from_host(client_data);
> > +}
> > +
> > +/**
> > + * loader_ishtp_cl_probe() - ISH-TP client driver probe
> > + * @cl_device:         ISH-TP client device instance
> > + *
> > + * This function gets called on device create on ISH-TP bus
> > + *
> > + * Return: 0 for success, negative error code for failure
> > + */
> > +static int loader_ishtp_cl_probe(struct ishtp_cl_device
> > *cl_device)
> > +{
> > +       struct ishtp_cl *loader_ishtp_cl;
> > +       struct ishtp_cl_data *client_data;
> > +       int rv;
> > +
> > +       client_data = devm_kzalloc(ishtp_device(cl_device),
> > +                                  sizeof(*client_data),
> > +                                  GFP_KERNEL);
> > +       if (!client_data)
> > +               return -ENOMEM;
> > +
> > +       loader_ishtp_cl = ishtp_cl_allocate(cl_device);
> > +       if (!loader_ishtp_cl)
> > +               return -ENOMEM;
> > +
> > +       ishtp_set_drvdata(cl_device, loader_ishtp_cl);
> > +       ishtp_set_client_data(loader_ishtp_cl, client_data);
> > +       client_data->loader_ishtp_cl = loader_ishtp_cl;
> > +       client_data->cl_device = cl_device;
> > +
> > +       init_waitqueue_head(&client_data->response.wait_queue);
> > +
> > +       INIT_WORK(&client_data->work_ishtp_reset,
> > +                 reset_handler);
> > +       INIT_WORK(&client_data->work_fw_load,
> > +                 load_fw_from_host_handler);
> > +
> > +       rv = loader_init(loader_ishtp_cl, 0);
> > +       if (rv < 0) {
> > +               ishtp_cl_free(loader_ishtp_cl);
> > +               return rv;
> > +       }
> > +       ishtp_get_device(cl_device);
> > +
> > +       client_data->retry_count = 0;
> > +
> > +       /* ISH firmware loading from host */
> > +       schedule_work(&client_data->work_fw_load);
> > +
> > +       return 0;
> > +}
> > +
> > +/**
> > + * loader_ishtp_cl_remove() - ISH-TP client driver remove
> > + * @cl_device:         ISH-TP client device instance
> > + *
> > + * This function gets called on device remove on ISH-TP bus
> > + *
> > + * Return: 0
> > + */
> > +static int loader_ishtp_cl_remove(struct ishtp_cl_device
> > *cl_device)
> > +{
> > +       struct ishtp_cl_data *client_data;
> > +       struct ishtp_cl *loader_ishtp_cl =
> > ishtp_get_drvdata(cl_device);
> > +
> > +       client_data = ishtp_get_client_data(loader_ishtp_cl);
> > +
> > +       /*
> > +        * The sequence of the following two cancel_work_sync() is
> > +        * important. The work_fw_load can in turn schedue
> > +        * work_ishtp_reset, so first cancel work_fw_load then
> > +        * cancel work_ishtp_reset.
> > +        */
> > +       cancel_work_sync(&client_data->work_fw_load);
> > +       cancel_work_sync(&client_data->work_ishtp_reset);
> > +       loader_deinit(loader_ishtp_cl);
> > +       ishtp_put_device(cl_device);
> > +
> > +       return 0;
> > +}
> > +
> > +/**
> > + * loader_ishtp_cl_reset() - ISH-TP client driver reset
> > + * @cl_device:         ISH-TP client device instance
> > + *
> > + * This function gets called on device reset on ISH-TP bus
> > + *
> > + * Return: 0
> > + */
> > +static int loader_ishtp_cl_reset(struct ishtp_cl_device
> > *cl_device)
> > +{
> > +       struct ishtp_cl_data *client_data;
> > +       struct ishtp_cl *loader_ishtp_cl =
> > ishtp_get_drvdata(cl_device);
> > +
> > +       client_data = ishtp_get_client_data(loader_ishtp_cl);
> > +
> > +       schedule_work(&client_data->work_ishtp_reset);
> > +
> > +       return 0;
> > +}
> > +
> > +static struct ishtp_cl_driver  loader_ishtp_cl_driver = {
> > +       .name = "ish-loader",
> > +       .guid = &loader_ishtp_guid,
> > +       .probe = loader_ishtp_cl_probe,
> > +       .remove = loader_ishtp_cl_remove,
> > +       .reset = loader_ishtp_cl_reset,
> > +};
> > +
> > +static int __init ish_loader_init(void)
> > +{
> > +       return ishtp_cl_driver_register(&loader_ishtp_cl_driver,
> > THIS_MODULE);
> > +}
> > +
> > +static void __exit ish_loader_exit(void)
> > +{
> > +       ishtp_cl_driver_unregister(&loader_ishtp_cl_driver);
> > +}
> > +
> > +late_initcall(ish_loader_init);
> > +module_exit(ish_loader_exit);
> > +
> > +module_param(dma_buf_size_limit, int, 0644);
> > +MODULE_PARM_DESC(dma_buf_size_limit, "Limit the DMA buf size to
> > this value in bytes");
> > +
> > +MODULE_DESCRIPTION("ISH ISH-TP Host firmware Loader Client
> > Driver");
> > +MODULE_AUTHOR("Rushikesh S Kadam <rushikesh.s.kadam@intel.com>");
> > +
> > +MODULE_LICENSE("GPL v2");
> > +MODULE_ALIAS("ishtp:*");
> > --
> > 1.9.1
> > 
> 
> Reviewed-by: Nick Crews <ncrews@chromium.org>