Re: [PATCH V1 1/4] scsi: ufs: query descriptor API

[Santosh Y <santoshsy@gmail.com>]

On Tue, May 27, 2014 at 12:51 PM, Dolev Raviv <draviv@codeaurora.org> wrote:
> Introduces the API for sending queries with descriptors.
> A descriptor is a block or page of parameters that describe the device.
> The descriptors are classified into types and can range in size
> from 2 bytes through 255 bytes.
> All descriptors have a length value as their first element, and a type
> identification element as their second byte.
> All descriptors are readable and some may be write once.
> They are accessed using their type, index and selector.
>
> Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
> Signed-off-by: Raviv Shvili <rshvili@codeaurora.org>
> ---
>  drivers/scsi/ufs/ufs.h    |  17 +++++-
>  drivers/scsi/ufs/ufshcd.c | 139 +++++++++++++++++++++++++++++++++++++---------
>  2 files changed, 128 insertions(+), 28 deletions(-)
>
> diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h
> index f42d1ce..1545cd7 100644
> --- a/drivers/scsi/ufs/ufs.h
> +++ b/drivers/scsi/ufs/ufs.h
> @@ -41,7 +41,8 @@
>
>  #define MAX_CDB_SIZE   16
>  #define GENERAL_UPIU_REQUEST_SIZE 32
> -#define QUERY_DESC_MAX_SIZE       256
> +#define QUERY_DESC_MAX_SIZE       255
> +#define QUERY_DESC_MIN_SIZE       2
>  #define QUERY_OSF_SIZE            (GENERAL_UPIU_REQUEST_SIZE - \
>                                         (sizeof(struct utp_upiu_header)))
>
> @@ -117,6 +118,20 @@ enum attr_idn {
>         QUERY_ATTR_IDN_EE_STATUS        = 0x0E,
>  };
>
> +/* Descriptor idn for Query requests */
> +enum desc_idn {
> +       QUERY_DESC_IDN_DEVICE           = 0x0,
> +       QUERY_DESC_IDN_CONFIGURAION     = 0x1,
> +       QUERY_DESC_IDN_UNIT             = 0x2,
> +       QUERY_DESC_IDN_RFU_0            = 0x3,
> +       QUERY_DESC_IDN_INTERCONNECT     = 0x4,
> +       QUERY_DESC_IDN_STRING           = 0x5,
> +       QUERY_DESC_IDN_RFU_1            = 0x6,
> +       QUERY_DESC_IDN_GEOMETRY         = 0x7,
> +       QUERY_DESC_IDN_POWER            = 0x8,
> +       QUERY_DESC_IDN_RFU_2            = 0x9,
> +};
> +
>  /* Exception event mask values */
>  enum {
>         MASK_EE_STATUS          = 0xFFFF,
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> index 0c28772..ed533f4 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -459,7 +459,7 @@ void ufshcd_copy_query_response(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
>
>         /* Get the descriptor */
>         if (lrbp->ucd_rsp_ptr->qr.opcode == UPIU_QUERY_OPCODE_READ_DESC) {
> -               u8 *descp = (u8 *)&lrbp->ucd_rsp_ptr +
> +               u8 *descp = (u8 *)lrbp->ucd_rsp_ptr +
>                                 GENERAL_UPIU_REQUEST_SIZE;
>                 u16 len;
>
> @@ -1134,6 +1134,30 @@ out_put_tag:
>  }
>
>  /**
> + * ufshcd_init_query() - init the query response and request parameters
> + * @hba: per-adapter instance
> + * @request: address of the request pointer to be initialized
> + * @response: address of the response pointer to be initialized
> + * @opcode: operation to perform
> + * @idn: flag idn to access
> + * @index: LU number to access
> + * @selector: query/flag/descriptor further identification
> + */
> +static inline void ufshcd_init_query(struct ufs_hba *hba,
> +               struct ufs_query_req **request, struct ufs_query_res **response,
> +               enum query_opcode opcode, u8 idn, u8 index, u8 selector)
> +{
> +       *request = &hba->dev_cmd.query.request;
> +       *response = &hba->dev_cmd.query.response;
> +       memset(*request, 0, sizeof(struct ufs_query_req));
> +       memset(*response, 0, sizeof(struct ufs_query_res));
> +       (*request)->upiu_req.opcode = opcode;
> +       (*request)->upiu_req.idn = idn;
> +       (*request)->upiu_req.index = index;
> +       (*request)->upiu_req.selector = selector;
> +}
> +
> +/**
>   * ufshcd_query_flag() - API function for sending flag query requests
>   * hba: per-adapter instance
>   * query_opcode: flag query to perform
> @@ -1145,17 +1169,15 @@ out_put_tag:
>  static int ufshcd_query_flag(struct ufs_hba *hba, enum query_opcode opcode,
>                         enum flag_idn idn, bool *flag_res)
>  {
> -       struct ufs_query_req *request;
> -       struct ufs_query_res *response;
> -       int err;
> +       struct ufs_query_req *request = NULL;
> +       struct ufs_query_res *response = NULL;
> +       int err, index = 0, selector = 0;
>
>         BUG_ON(!hba);
>
>         mutex_lock(&hba->dev_cmd.lock);
> -       request = &hba->dev_cmd.query.request;
> -       response = &hba->dev_cmd.query.response;
> -       memset(request, 0, sizeof(struct ufs_query_req));
> -       memset(response, 0, sizeof(struct ufs_query_res));
> +       ufshcd_init_query(hba, &request, &response, opcode, idn, index,
> +                       selector);
>
>         switch (opcode) {
>         case UPIU_QUERY_OPCODE_SET_FLAG:
> @@ -1180,12 +1202,8 @@ static int ufshcd_query_flag(struct ufs_hba *hba, enum query_opcode opcode,
>                 err = -EINVAL;
>                 goto out_unlock;
>         }
> -       request->upiu_req.opcode = opcode;
> -       request->upiu_req.idn = idn;
>
> -       /* Send query request */
> -       err = ufshcd_exec_dev_cmd(hba, DEV_CMD_TYPE_QUERY,
> -                       QUERY_REQ_TIMEOUT);
> +       err = ufshcd_exec_dev_cmd(hba, DEV_CMD_TYPE_QUERY, QUERY_REQ_TIMEOUT);
>
>         if (err) {
>                 dev_err(hba->dev,
> @@ -1217,8 +1235,8 @@ out_unlock:
>  static int ufshcd_query_attr(struct ufs_hba *hba, enum query_opcode opcode,
>                         enum attr_idn idn, u8 index, u8 selector, u32 *attr_val)
>  {
> -       struct ufs_query_req *request;
> -       struct ufs_query_res *response;
> +       struct ufs_query_req *request = NULL;
> +       struct ufs_query_res *response = NULL;
>         int err;
>
>         BUG_ON(!hba);
> @@ -1231,10 +1249,8 @@ static int ufshcd_query_attr(struct ufs_hba *hba, enum query_opcode opcode,
>         }
>
>         mutex_lock(&hba->dev_cmd.lock);
> -       request = &hba->dev_cmd.query.request;
> -       response = &hba->dev_cmd.query.response;
> -       memset(request, 0, sizeof(struct ufs_query_req));
> -       memset(response, 0, sizeof(struct ufs_query_res));
> +       ufshcd_init_query(hba, &request, &response, opcode, idn, index,
> +                       selector);
>
>         switch (opcode) {
>         case UPIU_QUERY_OPCODE_WRITE_ATTR:
> @@ -1251,14 +1267,7 @@ static int ufshcd_query_attr(struct ufs_hba *hba, enum query_opcode opcode,
>                 goto out_unlock;
>         }
>
> -       request->upiu_req.opcode = opcode;
> -       request->upiu_req.idn = idn;
> -       request->upiu_req.index = index;
> -       request->upiu_req.selector = selector;
> -
> -       /* Send query request */
> -       err = ufshcd_exec_dev_cmd(hba, DEV_CMD_TYPE_QUERY,
> -                                               QUERY_REQ_TIMEOUT);
> +       err = ufshcd_exec_dev_cmd(hba, DEV_CMD_TYPE_QUERY, QUERY_REQ_TIMEOUT);
>
>         if (err) {
>                 dev_err(hba->dev, "%s: opcode 0x%.2x for idn %d failed, err = %d\n",
> @@ -1275,6 +1284,82 @@ out:
>  }
>
>  /**
> + * ufshcd_query_descriptor - API function for sending descriptor requests
> + * hba: per-adapter instance
> + * opcode: attribute opcode
> + * idn: attribute idn to access
> + * index: index field
> + * selector: selector field
> + * desc_buf: the buffer that contains the descriptor
> + * buf_len: length parameter passed to the device
> + *
> + * Returns 0 for success, non-zero in case of failure.
> + * The buf_len parameter will contain, on return, the length parameter
> + * received on the response.
> + */
> +int ufshcd_query_descriptor(struct ufs_hba *hba,
> +                       enum query_opcode opcode, enum desc_idn idn, u8 index,
> +                       u8 selector, u8 *desc_buf, int *buf_len)
> +{
> +       struct ufs_query_req *request = NULL;
> +       struct ufs_query_res *response = NULL;
> +       int err;
> +
> +       BUG_ON(!hba);
> +
> +       if (!desc_buf) {
> +               dev_err(hba->dev, "%s: descriptor buffer required for opcode 0x%x\n",
> +                               __func__, opcode);
> +               err = -EINVAL;
> +               goto out;
> +       }
> +
> +       if (*buf_len <= QUERY_DESC_MIN_SIZE || *buf_len > QUERY_DESC_MAX_SIZE) {
> +               dev_err(hba->dev, "%s: descriptor buffer size (%d) is out of range\n",
> +                               __func__, *buf_len);
> +               err = -EINVAL;
> +               goto out;
> +       }
> +
> +       mutex_lock(&hba->dev_cmd.lock);
> +       ufshcd_init_query(hba, &request, &response, opcode, idn, index,
> +                       selector);
> +       hba->dev_cmd.query.descriptor = desc_buf;
> +       request->upiu_req.length = *buf_len;
> +
> +       switch (opcode) {
> +       case UPIU_QUERY_OPCODE_WRITE_DESC:
> +               request->query_func = UPIU_QUERY_FUNC_STANDARD_WRITE_REQUEST;
> +               break;
> +       case UPIU_QUERY_OPCODE_READ_DESC:
> +               request->query_func = UPIU_QUERY_FUNC_STANDARD_READ_REQUEST;
> +               break;
> +       default:
> +               dev_err(hba->dev,
> +                               "%s: Expected query descriptor opcode but got = 0x%.2x\n",
> +                               __func__, opcode);
> +               err = -EINVAL;
> +               goto out_unlock;
> +       }
> +
> +       err = ufshcd_exec_dev_cmd(hba, DEV_CMD_TYPE_QUERY, QUERY_REQ_TIMEOUT);
> +
> +       if (err) {
> +               dev_err(hba->dev, "%s: opcode 0x%.2x for idn %d failed, err = %d\n",
> +                               __func__, opcode, idn, err);
> +               goto out_unlock;
> +       }
> +
> +       hba->dev_cmd.query.descriptor = NULL;
> +       *buf_len = response->upiu_res.length;
> +
> +out_unlock:
> +       mutex_unlock(&hba->dev_cmd.lock);
> +out:
> +       return err;
> +}
> +
> +/**
>   * ufshcd_memory_alloc - allocate memory for host memory space data structures
>   * @hba: per adapter instance
>   *
> --
> 1.8.5.2
>

Acked-by: Santosh Y <santoshsy@gmail.com>

-- 
~Santosh