misc: bcm-vk: add ttyVK support

Add ttyVK support to driver to allow console access to VK card from host.

Device node will be in the follow form /dev/bcm-vk.x_ttyVKy where:
x is the instance of the VK card
y is the tty device number on the VK card

Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Scott Branden <scott.branden@broadcom.com>
Link: https://lore.kernel.org/r/20210120175827.14820-14-scott.branden@broadcom.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 28 insertions, 0 deletions

diff --git a/drivers/misc/bcm-vk/bcm_vk.h b/drivers/misc/bcm-vk/bcm_vk.h
index a1d0bf6e694c..3f37c640a814 100644
--- a/drivers/misc/bcm-vk/bcm_vk.h
+++ b/drivers/misc/bcm-vk/bcm_vk.h
@@ -8,12 +8,14 @@
 
 #include <linux/atomic.h>
 #include <linux/firmware.h>
+#include <linux/irq.h>
 #include <linux/kref.h>
 #include <linux/miscdevice.h>
 #include <linux/mutex.h>
 #include <linux/pci.h>
 #include <linux/poll.h>
 #include <linux/sched/signal.h>
+#include <linux/tty.h>
 #include <linux/uaccess.h>
 #include <uapi/linux/misc/bcm_vk.h>
 
@@ -84,6 +86,9 @@
 #define CODEPUSH_BOOT2_ENTRY		0x60000000
 
 #define BAR_CARD_STATUS			0x410
+/* CARD_STATUS definitions */
+#define CARD_STATUS_TTYVK0_READY	BIT(0)
+#define CARD_STATUS_TTYVK1_READY	BIT(1)
 
 #define BAR_BOOT1_STDALONE_PROGRESS	0x420
 #define BOOT1_STDALONE_SUCCESS		(BIT(13) | BIT(14))
@@ -255,6 +260,19 @@ enum pci_barno {
 
 #define BCM_VK_NUM_TTY 2
 
+struct bcm_vk_tty {
+	struct tty_port port;
+	u32 to_offset;	/* bar offset to use */
+	u32 to_size;	/* to VK buffer size */
+	u32 wr;		/* write offset shadow */
+	u32 from_offset;	/* bar offset to use */
+	u32 from_size;	/* from VK buffer size */
+	u32 rd;		/* read offset shadow */
+	pid_t pid;
+	bool irq_enabled;
+	bool is_opened;		/* tracks tty open/close */
+};
+
 /* VK device max power state, supports 3, full, reduced and low */
 #define MAX_OPP 3
 #define MAX_CARD_INFO_TAG_SIZE 64
@@ -348,6 +366,12 @@ struct bcm_vk {
 	struct miscdevice miscdev;
 	int devid; /* dev id allocated */
 
+	struct tty_driver *tty_drv;
+	struct timer_list serial_timer;
+	struct bcm_vk_tty tty[BCM_VK_NUM_TTY];
+	struct workqueue_struct *tty_wq_thread;
+	struct work_struct tty_wq_work;
+
 	/* Reference-counting to handle file operations */
 	struct kref kref;
 
@@ -466,6 +490,7 @@ int bcm_vk_release(struct inode *inode, struct file *p_file);
 void bcm_vk_release_data(struct kref *kref);
 irqreturn_t bcm_vk_msgq_irqhandler(int irq, void *dev_id);
 irqreturn_t bcm_vk_notf_irqhandler(int irq, void *dev_id);
+irqreturn_t bcm_vk_tty_irqhandler(int irq, void *dev_id);
 int bcm_vk_msg_init(struct bcm_vk *vk);
 void bcm_vk_msg_remove(struct bcm_vk *vk);
 void bcm_vk_drain_msg_on_reset(struct bcm_vk *vk);
@@ -476,6 +501,9 @@ int bcm_vk_send_shutdown_msg(struct bcm_vk *vk, u32 shut_type,
 			     const pid_t pid, const u32 q_num);
 void bcm_to_v_q_doorbell(struct bcm_vk *vk, u32 q_num, u32 db_val);
 int bcm_vk_auto_load_all_images(struct bcm_vk *vk);
+int bcm_vk_tty_init(struct bcm_vk *vk, char *name);
+void bcm_vk_tty_exit(struct bcm_vk *vk);
+void bcm_vk_tty_terminate_tty_user(struct bcm_vk *vk);
 void bcm_vk_hb_init(struct bcm_vk *vk);
 void bcm_vk_hb_deinit(struct bcm_vk *vk);
 void bcm_vk_handle_notf(struct bcm_vk *vk);