include/net/caif/caif_spi.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright (C) ST-Ericsson AB 2010
   4  * Author:      Daniel Martensson / Daniel.Martensson@stericsson.com
   5  */
   6
   7 #ifndef CAIF_SPI_H_
   8 #define CAIF_SPI_H_
   9
  10 #include <net/caif/caif_device.h>
  11
  12 #define SPI_CMD_WR                      0x00
  13 #define SPI_CMD_RD                      0x01
  14 #define SPI_CMD_EOT                     0x02
  15 #define SPI_CMD_IND                     0x04
  16
  17 #define SPI_DMA_BUF_LEN                 8192
  18
  19 #define WL_SZ                           2       /* 16 bits. */
  20 #define SPI_CMD_SZ                      4       /* 32 bits. */
  21 #define SPI_IND_SZ                      4       /* 32 bits. */
  22
  23 #define SPI_XFER                        0
  24 #define SPI_SS_ON                       1
  25 #define SPI_SS_OFF                      2
  26 #define SPI_TERMINATE                   3
  27
  28 /* Minimum time between different levels is 50 microseconds. */
  29 #define MIN_TRANSITION_TIME_USEC        50
  30
  31 /* Defines for calculating duration of SPI transfers for a particular
  32  * number of bytes.
  33  */
  34 #define SPI_MASTER_CLK_MHZ              13
  35 #define SPI_XFER_TIME_USEC(bytes, clk) (((bytes) * 8) / clk)
  36
  37 /* Normally this should be aligned on the modem in order to benefit from full
  38  * duplex transfers. However a size of 8188 provokes errors when running with
  39  * the modem. These errors occur when packet sizes approaches 4 kB of data.
  40  */
  41 #define CAIF_MAX_SPI_FRAME 4092
  42
  43 /* Maximum number of uplink CAIF frames that can reside in the same SPI frame.
  44  * This number should correspond with the modem setting. The application side
  45  * CAIF accepts any number of embedded downlink CAIF frames.
  46  */
  47 #define CAIF_MAX_SPI_PKTS 9
  48
  49 /* Decides if SPI buffers should be prefilled with 0xFF pattern for easier
  50  * debugging. Both TX and RX buffers will be filled before the transfer.
  51  */
  52 #define CFSPI_DBG_PREFILL               0
  53
  54 /* Structure describing a SPI transfer. */
  55 struct cfspi_xfer {
  56         u16 tx_dma_len;
  57         u16 rx_dma_len;
  58         void *va_tx[2];
  59         dma_addr_t pa_tx[2];
  60         void *va_rx;
  61         dma_addr_t pa_rx;
  62 };
  63
  64 /* Structure implemented by the SPI interface. */
  65 struct cfspi_ifc {
  66         void (*ss_cb) (bool assert, struct cfspi_ifc *ifc);
  67         void (*xfer_done_cb) (struct cfspi_ifc *ifc);
  68         void *priv;
  69 };
  70
  71 /* Structure implemented by SPI clients. */
  72 struct cfspi_dev {
  73         int (*init_xfer) (struct cfspi_xfer *xfer, struct cfspi_dev *dev);
  74         void (*sig_xfer) (bool xfer, struct cfspi_dev *dev);
  75         struct cfspi_ifc *ifc;
  76         char *name;
  77         u32 clk_mhz;
  78         void *priv;
  79 };
  80
  81 /* Enumeration describing the CAIF SPI state. */
  82 enum cfspi_state {
  83         CFSPI_STATE_WAITING = 0,
  84         CFSPI_STATE_AWAKE,
  85         CFSPI_STATE_FETCH_PKT,
  86         CFSPI_STATE_GET_NEXT,
  87         CFSPI_STATE_INIT_XFER,
  88         CFSPI_STATE_WAIT_ACTIVE,
  89         CFSPI_STATE_SIG_ACTIVE,
  90         CFSPI_STATE_WAIT_XFER_DONE,
  91         CFSPI_STATE_XFER_DONE,
  92         CFSPI_STATE_WAIT_INACTIVE,
  93         CFSPI_STATE_SIG_INACTIVE,
  94         CFSPI_STATE_DELIVER_PKT,
  95         CFSPI_STATE_MAX,
  96 };
  97
  98 /* Structure implemented by SPI physical interfaces. */
  99 struct cfspi {
 100         struct caif_dev_common cfdev;
 101         struct net_device *ndev;
 102         struct platform_device *pdev;
 103         struct sk_buff_head qhead;
 104         struct sk_buff_head chead;
 105         u16 cmd;
 106         u16 tx_cpck_len;
 107         u16 tx_npck_len;
 108         u16 rx_cpck_len;
 109         u16 rx_npck_len;
 110         struct cfspi_ifc ifc;
 111         struct cfspi_xfer xfer;
 112         struct cfspi_dev *dev;
 113         unsigned long state;
 114         struct work_struct work;
 115         struct workqueue_struct *wq;
 116         struct list_head list;
 117         int    flow_off_sent;
 118         u32 qd_low_mark;
 119         u32 qd_high_mark;
 120         struct completion comp;
 121         wait_queue_head_t wait;
 122         spinlock_t lock;
 123         bool flow_stop;
 124         bool slave;
 125         bool slave_talked;
 126 #ifdef CONFIG_DEBUG_FS
 127         enum cfspi_state dbg_state;
 128         u16 pcmd;
 129         u16 tx_ppck_len;
 130         u16 rx_ppck_len;
 131         struct dentry *dbgfs_dir;
 132         struct dentry *dbgfs_state;
 133         struct dentry *dbgfs_frame;
 134 #endif                          /* CONFIG_DEBUG_FS */
 135 };
 136
 137 extern int spi_frm_align;
 138 extern int spi_up_head_align;
 139 extern int spi_up_tail_align;
 140 extern int spi_down_head_align;
 141 extern int spi_down_tail_align;
 142 extern struct platform_driver cfspi_spi_driver;
 143
 144 void cfspi_dbg_state(struct cfspi *cfspi, int state);
 145 int cfspi_xmitfrm(struct cfspi *cfspi, u8 *buf, size_t len);
 146 int cfspi_xmitlen(struct cfspi *cfspi);
 147 int cfspi_rxfrm(struct cfspi *cfspi, u8 *buf, size_t len);
 148 int cfspi_spi_remove(struct platform_device *pdev);
 149 int cfspi_spi_probe(struct platform_device *pdev);
 150 int cfspi_xmitfrm(struct cfspi *cfspi, u8 *buf, size_t len);
 151 int cfspi_xmitlen(struct cfspi *cfspi);
 152 int cfspi_rxfrm(struct cfspi *cfspi, u8 *buf, size_t len);
 153 void cfspi_xfer(struct work_struct *work);
 154
 155 #endif                          /* CAIF_SPI_H_ */