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1080 lines
22 KiB
1080 lines
22 KiB
// SPDX-License-Identifier: GPL-2.0 |
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/* vcc.c: sun4v virtual channel concentrator |
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* |
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* Copyright (C) 2017 Oracle. All rights reserved. |
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*/ |
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|
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#include <linux/delay.h> |
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#include <linux/interrupt.h> |
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#include <linux/module.h> |
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#include <linux/slab.h> |
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#include <linux/sysfs.h> |
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#include <linux/tty.h> |
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#include <linux/tty_flip.h> |
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#include <asm/vio.h> |
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#include <asm/ldc.h> |
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MODULE_DESCRIPTION("Sun LDOM virtual console concentrator driver"); |
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MODULE_LICENSE("GPL"); |
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MODULE_VERSION("1.1"); |
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struct vcc_port { |
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struct vio_driver_state vio; |
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spinlock_t lock; |
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char *domain; |
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struct tty_struct *tty; /* only populated while dev is open */ |
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unsigned long index; /* index into the vcc_table */ |
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u64 refcnt; |
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bool excl_locked; |
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bool removed; |
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/* This buffer is required to support the tty write_room interface |
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* and guarantee that any characters that the driver accepts will |
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* be eventually sent, either immediately or later. |
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*/ |
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int chars_in_buffer; |
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struct vio_vcc buffer; |
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struct timer_list rx_timer; |
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struct timer_list tx_timer; |
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}; |
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/* Microseconds that thread will delay waiting for a vcc port ref */ |
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#define VCC_REF_DELAY 100 |
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#define VCC_MAX_PORTS 1024 |
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#define VCC_MINOR_START 0 /* must be zero */ |
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#define VCC_BUFF_LEN VIO_VCC_MTU_SIZE |
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#define VCC_CTL_BREAK -1 |
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#define VCC_CTL_HUP -2 |
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static struct tty_driver *vcc_tty_driver; |
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static struct vcc_port *vcc_table[VCC_MAX_PORTS]; |
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static DEFINE_SPINLOCK(vcc_table_lock); |
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static unsigned int vcc_dbg; |
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static unsigned int vcc_dbg_ldc; |
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static unsigned int vcc_dbg_vio; |
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module_param(vcc_dbg, uint, 0664); |
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module_param(vcc_dbg_ldc, uint, 0664); |
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module_param(vcc_dbg_vio, uint, 0664); |
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#define VCC_DBG_DRV 0x1 |
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#define VCC_DBG_LDC 0x2 |
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#define VCC_DBG_PKT 0x4 |
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#define vccdbg(f, a...) \ |
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do { \ |
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if (vcc_dbg & VCC_DBG_DRV) \ |
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pr_info(f, ## a); \ |
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} while (0) \ |
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#define vccdbgl(l) \ |
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do { \ |
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if (vcc_dbg & VCC_DBG_LDC) \ |
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ldc_print(l); \ |
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} while (0) \ |
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#define vccdbgp(pkt) \ |
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do { \ |
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if (vcc_dbg & VCC_DBG_PKT) { \ |
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int i; \ |
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for (i = 0; i < pkt.tag.stype; i++) \ |
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pr_info("[%c]", pkt.data[i]); \ |
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} \ |
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} while (0) \ |
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/* Note: Be careful when adding flags to this line discipline. Don't |
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* add anything that will cause echoing or we'll go into recursive |
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* loop echoing chars back and forth with the console drivers. |
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*/ |
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static const struct ktermios vcc_tty_termios = { |
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.c_iflag = IGNBRK | IGNPAR, |
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.c_oflag = OPOST, |
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.c_cflag = B38400 | CS8 | CREAD | HUPCL, |
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.c_cc = INIT_C_CC, |
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.c_ispeed = 38400, |
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.c_ospeed = 38400 |
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}; |
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/** |
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* vcc_table_add() - Add VCC port to the VCC table |
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* @port: pointer to the VCC port |
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* |
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* Return: index of the port in the VCC table on success, |
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* -1 on failure |
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*/ |
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static int vcc_table_add(struct vcc_port *port) |
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{ |
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unsigned long flags; |
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int i; |
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spin_lock_irqsave(&vcc_table_lock, flags); |
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for (i = VCC_MINOR_START; i < VCC_MAX_PORTS; i++) { |
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if (!vcc_table[i]) { |
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vcc_table[i] = port; |
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break; |
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} |
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} |
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spin_unlock_irqrestore(&vcc_table_lock, flags); |
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if (i < VCC_MAX_PORTS) |
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return i; |
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else |
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return -1; |
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} |
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/** |
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* vcc_table_remove() - Removes a VCC port from the VCC table |
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* @index: Index into the VCC table |
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*/ |
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static void vcc_table_remove(unsigned long index) |
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{ |
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unsigned long flags; |
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if (WARN_ON(index >= VCC_MAX_PORTS)) |
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return; |
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spin_lock_irqsave(&vcc_table_lock, flags); |
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vcc_table[index] = NULL; |
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spin_unlock_irqrestore(&vcc_table_lock, flags); |
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} |
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/** |
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* vcc_get() - Gets a reference to VCC port |
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* @index: Index into the VCC table |
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* @excl: Indicates if an exclusive access is requested |
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* |
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* Return: reference to the VCC port, if found |
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* NULL, if port not found |
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*/ |
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static struct vcc_port *vcc_get(unsigned long index, bool excl) |
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{ |
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struct vcc_port *port; |
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unsigned long flags; |
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try_again: |
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spin_lock_irqsave(&vcc_table_lock, flags); |
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port = vcc_table[index]; |
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if (!port) { |
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spin_unlock_irqrestore(&vcc_table_lock, flags); |
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return NULL; |
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} |
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if (!excl) { |
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if (port->excl_locked) { |
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spin_unlock_irqrestore(&vcc_table_lock, flags); |
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udelay(VCC_REF_DELAY); |
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goto try_again; |
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} |
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port->refcnt++; |
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spin_unlock_irqrestore(&vcc_table_lock, flags); |
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return port; |
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} |
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if (port->refcnt) { |
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spin_unlock_irqrestore(&vcc_table_lock, flags); |
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/* Threads wanting exclusive access will wait half the time, |
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* probably giving them higher priority in the case of |
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* multiple waiters. |
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*/ |
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udelay(VCC_REF_DELAY/2); |
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goto try_again; |
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} |
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port->refcnt++; |
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port->excl_locked = true; |
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spin_unlock_irqrestore(&vcc_table_lock, flags); |
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return port; |
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} |
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/** |
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* vcc_put() - Returns a reference to VCC port |
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* @port: pointer to VCC port |
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* @excl: Indicates if the returned reference is an exclusive reference |
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* |
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* Note: It's the caller's responsibility to ensure the correct value |
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* for the excl flag |
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*/ |
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static void vcc_put(struct vcc_port *port, bool excl) |
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{ |
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unsigned long flags; |
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if (!port) |
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return; |
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spin_lock_irqsave(&vcc_table_lock, flags); |
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/* check if caller attempted to put with the wrong flags */ |
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if (WARN_ON((excl && !port->excl_locked) || |
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(!excl && port->excl_locked))) |
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goto done; |
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port->refcnt--; |
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if (excl) |
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port->excl_locked = false; |
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done: |
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spin_unlock_irqrestore(&vcc_table_lock, flags); |
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} |
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/** |
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* vcc_get_ne() - Get a non-exclusive reference to VCC port |
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* @index: Index into the VCC table |
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* |
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* Gets a non-exclusive reference to VCC port, if it's not removed |
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* |
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* Return: pointer to the VCC port, if found |
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* NULL, if port not found |
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*/ |
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static struct vcc_port *vcc_get_ne(unsigned long index) |
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{ |
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struct vcc_port *port; |
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port = vcc_get(index, false); |
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if (port && port->removed) { |
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vcc_put(port, false); |
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return NULL; |
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} |
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return port; |
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} |
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static void vcc_kick_rx(struct vcc_port *port) |
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{ |
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struct vio_driver_state *vio = &port->vio; |
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assert_spin_locked(&port->lock); |
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if (!timer_pending(&port->rx_timer) && !port->removed) { |
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disable_irq_nosync(vio->vdev->rx_irq); |
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port->rx_timer.expires = (jiffies + 1); |
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add_timer(&port->rx_timer); |
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} |
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} |
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static void vcc_kick_tx(struct vcc_port *port) |
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{ |
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assert_spin_locked(&port->lock); |
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if (!timer_pending(&port->tx_timer) && !port->removed) { |
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port->tx_timer.expires = (jiffies + 1); |
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add_timer(&port->tx_timer); |
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} |
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} |
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static int vcc_rx_check(struct tty_struct *tty, int size) |
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{ |
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if (WARN_ON(!tty || !tty->port)) |
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return 1; |
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/* tty_buffer_request_room won't sleep because it uses |
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* GFP_ATOMIC flag to allocate buffer |
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*/ |
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if (test_bit(TTY_THROTTLED, &tty->flags) || |
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(tty_buffer_request_room(tty->port, VCC_BUFF_LEN) < VCC_BUFF_LEN)) |
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return 0; |
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return 1; |
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} |
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static int vcc_rx(struct tty_struct *tty, char *buf, int size) |
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{ |
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int len = 0; |
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if (WARN_ON(!tty || !tty->port)) |
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return len; |
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len = tty_insert_flip_string(tty->port, buf, size); |
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if (len) |
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tty_flip_buffer_push(tty->port); |
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return len; |
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} |
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static int vcc_ldc_read(struct vcc_port *port) |
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{ |
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struct vio_driver_state *vio = &port->vio; |
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struct tty_struct *tty; |
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struct vio_vcc pkt; |
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int rv = 0; |
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tty = port->tty; |
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if (!tty) { |
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rv = ldc_rx_reset(vio->lp); |
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vccdbg("VCC: reset rx q: rv=%d\n", rv); |
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goto done; |
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} |
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/* Read as long as LDC has incoming data. */ |
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while (1) { |
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if (!vcc_rx_check(tty, VIO_VCC_MTU_SIZE)) { |
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vcc_kick_rx(port); |
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break; |
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} |
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vccdbgl(vio->lp); |
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rv = ldc_read(vio->lp, &pkt, sizeof(pkt)); |
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if (rv <= 0) |
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break; |
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vccdbg("VCC: ldc_read()=%d\n", rv); |
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vccdbg("TAG [%02x:%02x:%04x:%08x]\n", |
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pkt.tag.type, pkt.tag.stype, |
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pkt.tag.stype_env, pkt.tag.sid); |
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if (pkt.tag.type == VIO_TYPE_DATA) { |
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vccdbgp(pkt); |
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/* vcc_rx_check ensures memory availability */ |
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vcc_rx(tty, pkt.data, pkt.tag.stype); |
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} else { |
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pr_err("VCC: unknown msg [%02x:%02x:%04x:%08x]\n", |
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pkt.tag.type, pkt.tag.stype, |
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pkt.tag.stype_env, pkt.tag.sid); |
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rv = -ECONNRESET; |
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break; |
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} |
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WARN_ON(rv != LDC_PACKET_SIZE); |
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} |
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done: |
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return rv; |
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} |
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static void vcc_rx_timer(struct timer_list *t) |
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{ |
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struct vcc_port *port = from_timer(port, t, rx_timer); |
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struct vio_driver_state *vio; |
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unsigned long flags; |
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int rv; |
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spin_lock_irqsave(&port->lock, flags); |
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port->rx_timer.expires = 0; |
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vio = &port->vio; |
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enable_irq(vio->vdev->rx_irq); |
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if (!port->tty || port->removed) |
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goto done; |
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rv = vcc_ldc_read(port); |
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if (rv == -ECONNRESET) |
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vio_conn_reset(vio); |
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done: |
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spin_unlock_irqrestore(&port->lock, flags); |
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vcc_put(port, false); |
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} |
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static void vcc_tx_timer(struct timer_list *t) |
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{ |
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struct vcc_port *port = from_timer(port, t, tx_timer); |
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struct vio_vcc *pkt; |
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unsigned long flags; |
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int tosend = 0; |
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int rv; |
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spin_lock_irqsave(&port->lock, flags); |
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port->tx_timer.expires = 0; |
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if (!port->tty || port->removed) |
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goto done; |
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tosend = min(VCC_BUFF_LEN, port->chars_in_buffer); |
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if (!tosend) |
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goto done; |
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pkt = &port->buffer; |
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pkt->tag.type = VIO_TYPE_DATA; |
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pkt->tag.stype = tosend; |
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vccdbgl(port->vio.lp); |
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rv = ldc_write(port->vio.lp, pkt, (VIO_TAG_SIZE + tosend)); |
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WARN_ON(!rv); |
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if (rv < 0) { |
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vccdbg("VCC: ldc_write()=%d\n", rv); |
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vcc_kick_tx(port); |
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} else { |
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struct tty_struct *tty = port->tty; |
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port->chars_in_buffer = 0; |
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if (tty) |
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tty_wakeup(tty); |
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} |
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done: |
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spin_unlock_irqrestore(&port->lock, flags); |
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vcc_put(port, false); |
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} |
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/** |
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* vcc_event() - LDC event processing engine |
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* @arg: VCC private data |
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* @event: LDC event |
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* |
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* Handles LDC events for VCC |
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*/ |
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static void vcc_event(void *arg, int event) |
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{ |
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struct vio_driver_state *vio; |
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struct vcc_port *port; |
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unsigned long flags; |
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int rv; |
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port = arg; |
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vio = &port->vio; |
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spin_lock_irqsave(&port->lock, flags); |
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switch (event) { |
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case LDC_EVENT_RESET: |
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case LDC_EVENT_UP: |
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vio_link_state_change(vio, event); |
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break; |
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case LDC_EVENT_DATA_READY: |
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rv = vcc_ldc_read(port); |
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if (rv == -ECONNRESET) |
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vio_conn_reset(vio); |
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break; |
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default: |
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pr_err("VCC: unexpected LDC event(%d)\n", event); |
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} |
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spin_unlock_irqrestore(&port->lock, flags); |
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} |
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static struct ldc_channel_config vcc_ldc_cfg = { |
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.event = vcc_event, |
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.mtu = VIO_VCC_MTU_SIZE, |
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.mode = LDC_MODE_RAW, |
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.debug = 0, |
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}; |
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/* Ordered from largest major to lowest */ |
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static struct vio_version vcc_versions[] = { |
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{ .major = 1, .minor = 0 }, |
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}; |
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static struct tty_port_operations vcc_port_ops = { 0 }; |
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static ssize_t domain_show(struct device *dev, |
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struct device_attribute *attr, |
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char *buf) |
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{ |
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struct vcc_port *port; |
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int rv; |
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port = dev_get_drvdata(dev); |
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if (!port) |
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return -ENODEV; |
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rv = scnprintf(buf, PAGE_SIZE, "%s\n", port->domain); |
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return rv; |
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} |
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static int vcc_send_ctl(struct vcc_port *port, int ctl) |
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{ |
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struct vio_vcc pkt; |
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int rv; |
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pkt.tag.type = VIO_TYPE_CTRL; |
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pkt.tag.sid = ctl; |
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pkt.tag.stype = 0; |
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rv = ldc_write(port->vio.lp, &pkt, sizeof(pkt.tag)); |
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WARN_ON(!rv); |
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vccdbg("VCC: ldc_write(%ld)=%d\n", sizeof(pkt.tag), rv); |
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return rv; |
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} |
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static ssize_t break_store(struct device *dev, |
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struct device_attribute *attr, |
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const char *buf, size_t count) |
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{ |
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struct vcc_port *port; |
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unsigned long flags; |
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int rv = count; |
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int brk; |
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port = dev_get_drvdata(dev); |
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if (!port) |
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return -ENODEV; |
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spin_lock_irqsave(&port->lock, flags); |
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if (sscanf(buf, "%ud", &brk) != 1 || brk != 1) |
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rv = -EINVAL; |
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else if (vcc_send_ctl(port, VCC_CTL_BREAK) < 0) |
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vcc_kick_tx(port); |
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spin_unlock_irqrestore(&port->lock, flags); |
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return rv; |
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} |
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static DEVICE_ATTR_ADMIN_RO(domain); |
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static DEVICE_ATTR_WO(break); |
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static struct attribute *vcc_sysfs_entries[] = { |
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&dev_attr_domain.attr, |
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&dev_attr_break.attr, |
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NULL |
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}; |
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static struct attribute_group vcc_attribute_group = { |
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.name = NULL, |
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.attrs = vcc_sysfs_entries, |
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}; |
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|
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/** |
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* vcc_probe() - Initialize VCC port |
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* @vdev: Pointer to VIO device of the new VCC port |
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* @id: VIO device ID |
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* |
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* Initializes a VCC port to receive serial console data from |
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* the guest domain. Sets up a TTY end point on the control |
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* domain. Sets up VIO/LDC link between the guest & control |
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* domain endpoints. |
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* |
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* Return: status of the probe |
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*/ |
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static int vcc_probe(struct vio_dev *vdev, const struct vio_device_id *id) |
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{ |
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struct mdesc_handle *hp; |
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struct vcc_port *port; |
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struct device *dev; |
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const char *domain; |
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char *name; |
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u64 node; |
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int rv; |
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vccdbg("VCC: name=%s\n", dev_name(&vdev->dev)); |
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if (!vcc_tty_driver) { |
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pr_err("VCC: TTY driver not registered\n"); |
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return -ENODEV; |
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} |
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port = kzalloc(sizeof(struct vcc_port), GFP_KERNEL); |
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if (!port) |
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return -ENOMEM; |
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name = kstrdup(dev_name(&vdev->dev), GFP_KERNEL); |
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rv = vio_driver_init(&port->vio, vdev, VDEV_CONSOLE_CON, vcc_versions, |
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ARRAY_SIZE(vcc_versions), NULL, name); |
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if (rv) |
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goto free_port; |
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port->vio.debug = vcc_dbg_vio; |
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vcc_ldc_cfg.debug = vcc_dbg_ldc; |
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rv = vio_ldc_alloc(&port->vio, &vcc_ldc_cfg, port); |
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if (rv) |
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goto free_port; |
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spin_lock_init(&port->lock); |
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port->index = vcc_table_add(port); |
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if (port->index == -1) { |
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pr_err("VCC: no more TTY indices left for allocation\n"); |
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rv = -ENOMEM; |
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goto free_ldc; |
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} |
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/* Register the device using VCC table index as TTY index */ |
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dev = tty_register_device(vcc_tty_driver, port->index, &vdev->dev); |
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if (IS_ERR(dev)) { |
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rv = PTR_ERR(dev); |
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goto free_table; |
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} |
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|
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hp = mdesc_grab(); |
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|
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node = vio_vdev_node(hp, vdev); |
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if (node == MDESC_NODE_NULL) { |
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rv = -ENXIO; |
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mdesc_release(hp); |
|
goto unreg_tty; |
|
} |
|
|
|
domain = mdesc_get_property(hp, node, "vcc-domain-name", NULL); |
|
if (!domain) { |
|
rv = -ENXIO; |
|
mdesc_release(hp); |
|
goto unreg_tty; |
|
} |
|
port->domain = kstrdup(domain, GFP_KERNEL); |
|
|
|
mdesc_release(hp); |
|
|
|
rv = sysfs_create_group(&vdev->dev.kobj, &vcc_attribute_group); |
|
if (rv) |
|
goto free_domain; |
|
|
|
timer_setup(&port->rx_timer, vcc_rx_timer, 0); |
|
timer_setup(&port->tx_timer, vcc_tx_timer, 0); |
|
|
|
dev_set_drvdata(&vdev->dev, port); |
|
|
|
/* It's possible to receive IRQs in the middle of vio_port_up. Disable |
|
* IRQs until the port is up. |
|
*/ |
|
disable_irq_nosync(vdev->rx_irq); |
|
vio_port_up(&port->vio); |
|
enable_irq(vdev->rx_irq); |
|
|
|
return 0; |
|
|
|
free_domain: |
|
kfree(port->domain); |
|
unreg_tty: |
|
tty_unregister_device(vcc_tty_driver, port->index); |
|
free_table: |
|
vcc_table_remove(port->index); |
|
free_ldc: |
|
vio_ldc_free(&port->vio); |
|
free_port: |
|
kfree(name); |
|
kfree(port); |
|
|
|
return rv; |
|
} |
|
|
|
/** |
|
* vcc_remove() - Terminate a VCC port |
|
* @vdev: Pointer to VIO device of the VCC port |
|
* |
|
* Terminates a VCC port. Sets up the teardown of TTY and |
|
* VIO/LDC link between guest and primary domains. |
|
* |
|
* Return: status of removal |
|
*/ |
|
static void vcc_remove(struct vio_dev *vdev) |
|
{ |
|
struct vcc_port *port = dev_get_drvdata(&vdev->dev); |
|
|
|
del_timer_sync(&port->rx_timer); |
|
del_timer_sync(&port->tx_timer); |
|
|
|
/* If there's a process with the device open, do a synchronous |
|
* hangup of the TTY. This *may* cause the process to call close |
|
* asynchronously, but it's not guaranteed. |
|
*/ |
|
if (port->tty) |
|
tty_vhangup(port->tty); |
|
|
|
/* Get exclusive reference to VCC, ensures that there are no other |
|
* clients to this port. This cannot fail. |
|
*/ |
|
vcc_get(port->index, true); |
|
|
|
tty_unregister_device(vcc_tty_driver, port->index); |
|
|
|
del_timer_sync(&port->vio.timer); |
|
vio_ldc_free(&port->vio); |
|
sysfs_remove_group(&vdev->dev.kobj, &vcc_attribute_group); |
|
dev_set_drvdata(&vdev->dev, NULL); |
|
if (port->tty) { |
|
port->removed = true; |
|
vcc_put(port, true); |
|
} else { |
|
vcc_table_remove(port->index); |
|
|
|
kfree(port->vio.name); |
|
kfree(port->domain); |
|
kfree(port); |
|
} |
|
} |
|
|
|
static const struct vio_device_id vcc_match[] = { |
|
{ |
|
.type = "vcc-port", |
|
}, |
|
{}, |
|
}; |
|
MODULE_DEVICE_TABLE(vio, vcc_match); |
|
|
|
static struct vio_driver vcc_driver = { |
|
.id_table = vcc_match, |
|
.probe = vcc_probe, |
|
.remove = vcc_remove, |
|
.name = "vcc", |
|
}; |
|
|
|
static int vcc_open(struct tty_struct *tty, struct file *vcc_file) |
|
{ |
|
struct vcc_port *port; |
|
|
|
if (tty->count > 1) |
|
return -EBUSY; |
|
|
|
port = vcc_get_ne(tty->index); |
|
if (unlikely(!port)) { |
|
pr_err("VCC: open: Failed to find VCC port\n"); |
|
return -ENODEV; |
|
} |
|
|
|
if (unlikely(!port->vio.lp)) { |
|
pr_err("VCC: open: LDC channel not configured\n"); |
|
vcc_put(port, false); |
|
return -EPIPE; |
|
} |
|
vccdbgl(port->vio.lp); |
|
|
|
vcc_put(port, false); |
|
|
|
if (unlikely(!tty->port)) { |
|
pr_err("VCC: open: TTY port not found\n"); |
|
return -ENXIO; |
|
} |
|
|
|
if (unlikely(!tty->port->ops)) { |
|
pr_err("VCC: open: TTY ops not defined\n"); |
|
return -ENXIO; |
|
} |
|
|
|
return tty_port_open(tty->port, tty, vcc_file); |
|
} |
|
|
|
static void vcc_close(struct tty_struct *tty, struct file *vcc_file) |
|
{ |
|
if (unlikely(tty->count > 1)) |
|
return; |
|
|
|
if (unlikely(!tty->port)) { |
|
pr_err("VCC: close: TTY port not found\n"); |
|
return; |
|
} |
|
|
|
tty_port_close(tty->port, tty, vcc_file); |
|
} |
|
|
|
static void vcc_ldc_hup(struct vcc_port *port) |
|
{ |
|
unsigned long flags; |
|
|
|
spin_lock_irqsave(&port->lock, flags); |
|
|
|
if (vcc_send_ctl(port, VCC_CTL_HUP) < 0) |
|
vcc_kick_tx(port); |
|
|
|
spin_unlock_irqrestore(&port->lock, flags); |
|
} |
|
|
|
static void vcc_hangup(struct tty_struct *tty) |
|
{ |
|
struct vcc_port *port; |
|
|
|
port = vcc_get_ne(tty->index); |
|
if (unlikely(!port)) { |
|
pr_err("VCC: hangup: Failed to find VCC port\n"); |
|
return; |
|
} |
|
|
|
if (unlikely(!tty->port)) { |
|
pr_err("VCC: hangup: TTY port not found\n"); |
|
vcc_put(port, false); |
|
return; |
|
} |
|
|
|
vcc_ldc_hup(port); |
|
|
|
vcc_put(port, false); |
|
|
|
tty_port_hangup(tty->port); |
|
} |
|
|
|
static int vcc_write(struct tty_struct *tty, const unsigned char *buf, |
|
int count) |
|
{ |
|
struct vcc_port *port; |
|
struct vio_vcc *pkt; |
|
unsigned long flags; |
|
int total_sent = 0; |
|
int tosend = 0; |
|
int rv = -EINVAL; |
|
|
|
port = vcc_get_ne(tty->index); |
|
if (unlikely(!port)) { |
|
pr_err("VCC: write: Failed to find VCC port"); |
|
return -ENODEV; |
|
} |
|
|
|
spin_lock_irqsave(&port->lock, flags); |
|
|
|
pkt = &port->buffer; |
|
pkt->tag.type = VIO_TYPE_DATA; |
|
|
|
while (count > 0) { |
|
/* Minimum of data to write and space available */ |
|
tosend = min(count, (VCC_BUFF_LEN - port->chars_in_buffer)); |
|
|
|
if (!tosend) |
|
break; |
|
|
|
memcpy(&pkt->data[port->chars_in_buffer], &buf[total_sent], |
|
tosend); |
|
port->chars_in_buffer += tosend; |
|
pkt->tag.stype = tosend; |
|
|
|
vccdbg("TAG [%02x:%02x:%04x:%08x]\n", pkt->tag.type, |
|
pkt->tag.stype, pkt->tag.stype_env, pkt->tag.sid); |
|
vccdbg("DATA [%s]\n", pkt->data); |
|
vccdbgl(port->vio.lp); |
|
|
|
/* Since we know we have enough room in VCC buffer for tosend |
|
* we record that it was sent regardless of whether the |
|
* hypervisor actually took it because we have it buffered. |
|
*/ |
|
rv = ldc_write(port->vio.lp, pkt, (VIO_TAG_SIZE + tosend)); |
|
vccdbg("VCC: write: ldc_write(%d)=%d\n", |
|
(VIO_TAG_SIZE + tosend), rv); |
|
|
|
total_sent += tosend; |
|
count -= tosend; |
|
if (rv < 0) { |
|
vcc_kick_tx(port); |
|
break; |
|
} |
|
|
|
port->chars_in_buffer = 0; |
|
} |
|
|
|
spin_unlock_irqrestore(&port->lock, flags); |
|
|
|
vcc_put(port, false); |
|
|
|
vccdbg("VCC: write: total=%d rv=%d", total_sent, rv); |
|
|
|
return total_sent ? total_sent : rv; |
|
} |
|
|
|
static unsigned int vcc_write_room(struct tty_struct *tty) |
|
{ |
|
struct vcc_port *port; |
|
unsigned int num; |
|
|
|
port = vcc_get_ne(tty->index); |
|
if (unlikely(!port)) { |
|
pr_err("VCC: write_room: Failed to find VCC port\n"); |
|
return 0; |
|
} |
|
|
|
num = VCC_BUFF_LEN - port->chars_in_buffer; |
|
|
|
vcc_put(port, false); |
|
|
|
return num; |
|
} |
|
|
|
static unsigned int vcc_chars_in_buffer(struct tty_struct *tty) |
|
{ |
|
struct vcc_port *port; |
|
unsigned int num; |
|
|
|
port = vcc_get_ne(tty->index); |
|
if (unlikely(!port)) { |
|
pr_err("VCC: chars_in_buffer: Failed to find VCC port\n"); |
|
return 0; |
|
} |
|
|
|
num = port->chars_in_buffer; |
|
|
|
vcc_put(port, false); |
|
|
|
return num; |
|
} |
|
|
|
static int vcc_break_ctl(struct tty_struct *tty, int state) |
|
{ |
|
struct vcc_port *port; |
|
unsigned long flags; |
|
|
|
port = vcc_get_ne(tty->index); |
|
if (unlikely(!port)) { |
|
pr_err("VCC: break_ctl: Failed to find VCC port\n"); |
|
return -ENODEV; |
|
} |
|
|
|
/* Turn off break */ |
|
if (state == 0) { |
|
vcc_put(port, false); |
|
return 0; |
|
} |
|
|
|
spin_lock_irqsave(&port->lock, flags); |
|
|
|
if (vcc_send_ctl(port, VCC_CTL_BREAK) < 0) |
|
vcc_kick_tx(port); |
|
|
|
spin_unlock_irqrestore(&port->lock, flags); |
|
|
|
vcc_put(port, false); |
|
|
|
return 0; |
|
} |
|
|
|
static int vcc_install(struct tty_driver *driver, struct tty_struct *tty) |
|
{ |
|
struct vcc_port *port_vcc; |
|
struct tty_port *port_tty; |
|
int ret; |
|
|
|
if (tty->index >= VCC_MAX_PORTS) |
|
return -EINVAL; |
|
|
|
ret = tty_standard_install(driver, tty); |
|
if (ret) |
|
return ret; |
|
|
|
port_tty = kzalloc(sizeof(struct tty_port), GFP_KERNEL); |
|
if (!port_tty) |
|
return -ENOMEM; |
|
|
|
port_vcc = vcc_get(tty->index, true); |
|
if (!port_vcc) { |
|
pr_err("VCC: install: Failed to find VCC port\n"); |
|
tty->port = NULL; |
|
kfree(port_tty); |
|
return -ENODEV; |
|
} |
|
|
|
tty_port_init(port_tty); |
|
port_tty->ops = &vcc_port_ops; |
|
tty->port = port_tty; |
|
|
|
port_vcc->tty = tty; |
|
|
|
vcc_put(port_vcc, true); |
|
|
|
return 0; |
|
} |
|
|
|
static void vcc_cleanup(struct tty_struct *tty) |
|
{ |
|
struct vcc_port *port; |
|
|
|
port = vcc_get(tty->index, true); |
|
if (port) { |
|
port->tty = NULL; |
|
|
|
if (port->removed) { |
|
vcc_table_remove(tty->index); |
|
kfree(port->vio.name); |
|
kfree(port->domain); |
|
kfree(port); |
|
} else { |
|
vcc_put(port, true); |
|
} |
|
} |
|
|
|
tty_port_destroy(tty->port); |
|
kfree(tty->port); |
|
tty->port = NULL; |
|
} |
|
|
|
static const struct tty_operations vcc_ops = { |
|
.open = vcc_open, |
|
.close = vcc_close, |
|
.hangup = vcc_hangup, |
|
.write = vcc_write, |
|
.write_room = vcc_write_room, |
|
.chars_in_buffer = vcc_chars_in_buffer, |
|
.break_ctl = vcc_break_ctl, |
|
.install = vcc_install, |
|
.cleanup = vcc_cleanup, |
|
}; |
|
|
|
#define VCC_TTY_FLAGS (TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_REAL_RAW) |
|
|
|
static int vcc_tty_init(void) |
|
{ |
|
int rv; |
|
|
|
vcc_tty_driver = tty_alloc_driver(VCC_MAX_PORTS, VCC_TTY_FLAGS); |
|
if (IS_ERR(vcc_tty_driver)) { |
|
pr_err("VCC: TTY driver alloc failed\n"); |
|
return PTR_ERR(vcc_tty_driver); |
|
} |
|
|
|
vcc_tty_driver->driver_name = "vcc"; |
|
vcc_tty_driver->name = "vcc"; |
|
|
|
vcc_tty_driver->minor_start = VCC_MINOR_START; |
|
vcc_tty_driver->type = TTY_DRIVER_TYPE_SYSTEM; |
|
vcc_tty_driver->init_termios = vcc_tty_termios; |
|
|
|
tty_set_operations(vcc_tty_driver, &vcc_ops); |
|
|
|
rv = tty_register_driver(vcc_tty_driver); |
|
if (rv) { |
|
pr_err("VCC: TTY driver registration failed\n"); |
|
tty_driver_kref_put(vcc_tty_driver); |
|
vcc_tty_driver = NULL; |
|
return rv; |
|
} |
|
|
|
vccdbg("VCC: TTY driver registered\n"); |
|
|
|
return 0; |
|
} |
|
|
|
static void vcc_tty_exit(void) |
|
{ |
|
tty_unregister_driver(vcc_tty_driver); |
|
tty_driver_kref_put(vcc_tty_driver); |
|
vccdbg("VCC: TTY driver unregistered\n"); |
|
|
|
vcc_tty_driver = NULL; |
|
} |
|
|
|
static int __init vcc_init(void) |
|
{ |
|
int rv; |
|
|
|
rv = vcc_tty_init(); |
|
if (rv) { |
|
pr_err("VCC: TTY init failed\n"); |
|
return rv; |
|
} |
|
|
|
rv = vio_register_driver(&vcc_driver); |
|
if (rv) { |
|
pr_err("VCC: VIO driver registration failed\n"); |
|
vcc_tty_exit(); |
|
} else { |
|
vccdbg("VCC: VIO driver registered successfully\n"); |
|
} |
|
|
|
return rv; |
|
} |
|
|
|
static void __exit vcc_exit(void) |
|
{ |
|
vio_unregister_driver(&vcc_driver); |
|
vccdbg("VCC: VIO driver unregistered\n"); |
|
vcc_tty_exit(); |
|
vccdbg("VCC: TTY driver unregistered\n"); |
|
} |
|
|
|
module_init(vcc_init); |
|
module_exit(vcc_exit);
|
|
|