/* SPDX-License-Identifier: GPL-2.0-only */
/* OMAP SSI internal interface.
 *
 * Copyright (C) 2010 Nokia Corporation. All rights reserved.
 * Copyright (C) 2013 Sebastian Reichel
 *
 * Contact: Carlos Chinea <carlos.chinea@nokia.com>
 */

#ifndef __LINUX_HSI_OMAP_SSI_H__
#define __LINUX_HSI_OMAP_SSI_H__

#include <linux/device.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/hsi/hsi.h>
#include <linux/gpio/consumer.h>
#include <linux/interrupt.h>
#include <linux/io.h>

#define SSI_MAX_CHANNELS        8
#define SSI_MAX_GDD_LCH         8
#define SSI_BYTES_TO_FRAMES(x) ((((x) - 1) >> 2) + 1)

#define SSI_WAKE_EN 0

/**
 * struct omap_ssm_ctx - OMAP synchronous serial module (TX/RX) context
 * @mode: Bit transmission mode
 * @channels: Number of channels
 * @framesize: Frame size in bits
 * @timeout: RX frame timeout
 * @divisor: TX divider
 * @arb_mode: Arbitration mode for TX frame (Round robin, priority)
 */
struct omap_ssm_ctx {
        u32     mode;
        u32     channels;
        u32     frame_size;
        union   {
                        u32     timeout; /* Rx Only */
                        struct  {
                                        u32     arb_mode;
                                        u32     divisor;
                        }; /* Tx only */
        };
};

/**
 * struct omap_ssi_port - OMAP SSI port data
 * @dev: device associated to the port (HSI port)
 * @pdev: platform device associated to the port
 * @sst_dma: SSI transmitter physical base address
 * @ssr_dma: SSI receiver physical base address
 * @sst_base: SSI transmitter base address
 * @ssr_base: SSI receiver base address
 * @wk_lock: spin lock to serialize access to the wake lines
 * @lock: Spin lock to serialize access to the SSI port
 * @channels: Current number of channels configured (1,2,4 or 8)
 * @txqueue: TX message queues
 * @rxqueue: RX message queues
 * @brkqueue: Queue of incoming HWBREAK requests (FRAME mode)
 * @errqueue: Queue for failed messages
 * @errqueue_work: Delayed Work for failed messages
 * @irq: IRQ number
 * @wake_irq: IRQ number for incoming wake line (-1 if none)
 * @wake_gpio: GPIO number for incoming wake line (-1 if none)
 * @flags: flags to keep track of states
 * @wk_refcount: Reference count for output wake line
 * @work: worker for starting TX
 * @sys_mpu_enable: Context for the interrupt enable register for irq 0
 * @sst: Context for the synchronous serial transmitter
 * @ssr: Context for the synchronous serial receiver
 */
struct omap_ssi_port {
        struct device           *dev;
        struct device           *pdev;
        dma_addr_t              sst_dma;
        dma_addr_t              ssr_dma;
        void __iomem            *sst_base;
        void __iomem            *ssr_base;
        spinlock_t              wk_lock;
        spinlock_t              lock;
        unsigned int            channels;
        struct list_head        txqueue[SSI_MAX_CHANNELS];
        struct list_head        rxqueue[SSI_MAX_CHANNELS];
        struct list_head        brkqueue;
        struct list_head        errqueue;
        struct delayed_work     errqueue_work;
        unsigned int            irq;
        int                     wake_irq;
        struct gpio_desc        *wake_gpio;
        bool                    wktest:1; /* FIXME: HACK to be removed */
        unsigned long           flags;
        unsigned int            wk_refcount;
        struct work_struct      work;
        /* OMAP SSI port context */
        u32                     sys_mpu_enable; /* We use only one irq */
        struct omap_ssm_ctx     sst;
        struct omap_ssm_ctx     ssr;
        u32                     loss_count;
        u32                     port_id;
#ifdef CONFIG_DEBUG_FS
        struct dentry *dir;
#endif
};

/**
 * struct gdd_trn - GDD transaction data
 * @msg: Pointer to the HSI message being served
 * @sg: Pointer to the current sg entry being served
 */
struct gdd_trn {
        struct hsi_msg          *msg;
        struct scatterlist      *sg;
};

/**
 * struct omap_ssi_controller - OMAP SSI controller data
 * @dev: device associated to the controller (HSI controller)
 * @sys: SSI I/O base address
 * @gdd: GDD I/O base address
 * @fck: SSI functional clock
 * @gdd_irq: IRQ line for GDD
 * @gdd_tasklet: bottom half for DMA transfers
 * @gdd_trn: Array of GDD transaction data for ongoing GDD transfers
 * @lock: lock to serialize access to GDD
 * @fck_nb: DVFS notfifier block
 * @fck_rate: clock rate
 * @loss_count: To follow if we need to restore context or not
 * @max_speed: Maximum TX speed (Kb/s) set by the clients.
 * @gdd_gcr: SSI GDD saved context
 * @get_loss: Pointer to omap_pm_get_dev_context_loss_count, if any
 * @port: Array of pointers of the ports of the controller
 * @dir: Debugfs SSI root directory
 */
struct omap_ssi_controller {
        struct device           *dev;
        void __iomem            *sys;
        void __iomem            *gdd;
        struct clk              *fck;
        unsigned int            gdd_irq;
        struct tasklet_struct   gdd_tasklet;
        struct gdd_trn          gdd_trn[SSI_MAX_GDD_LCH];
        spinlock_t              lock;
        struct notifier_block   fck_nb;
        unsigned long           fck_rate;
        u32                     loss_count;
        u32                     max_speed;
        /* OMAP SSI Controller context */
        u32                     gdd_gcr;
        int                     (*get_loss)(struct device *dev);
        struct omap_ssi_port    **port;
#ifdef CONFIG_DEBUG_FS
        struct dentry *dir;
#endif
};

void omap_ssi_port_update_fclk(struct hsi_controller *ssi,
                               struct omap_ssi_port *omap_port);

extern struct platform_driver ssi_port_pdriver;

#endif /* __LINUX_HSI_OMAP_SSI_H__ */