From 8cf31a99d3a53a68f7032452cb7de3203b8200c8 Mon Sep 17 00:00:00 2001 From: Kumaravel Thiagarajan Date: Tue, 7 Feb 2023 22:18:14 +0530 Subject: serial: 8250_pci1xxxx: Add power management functions to quad-uart driver pci1xxxx's quad-uart function has the capability to wake up UART from suspend state. Enable wakeup before entering into suspend and disable wakeup on resume. Co-developed-by: Tharun Kumar P Signed-off-by: Tharun Kumar P Signed-off-by: Kumaravel Thiagarajan Link: https://lore.kernel.org/r/20230207164814.3104605-5-kumaravel.thiagarajan@microchip.com Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250_pci1xxxx.c | 115 ++++++++++++++++++++++++++++++++ 1 file changed, 115 insertions(+) (limited to 'drivers/tty') diff --git a/drivers/tty/serial/8250/8250_pci1xxxx.c b/drivers/tty/serial/8250/8250_pci1xxxx.c index 58f47d18f7d8..a3b25779d921 100644 --- a/drivers/tty/serial/8250/8250_pci1xxxx.c +++ b/drivers/tty/serial/8250/8250_pci1xxxx.c @@ -212,6 +212,116 @@ static const struct serial_rs485 pci1xxxx_rs485_supported = { /* Delay RTS before send is not supported */ }; +static bool pci1xxxx_port_suspend(int line) +{ + struct uart_8250_port *up = serial8250_get_port(line); + struct uart_port *port = &up->port; + struct tty_port *tport = &port->state->port; + unsigned long flags; + bool ret = false; + u8 wakeup_mask; + + mutex_lock(&tport->mutex); + if (port->suspended == 0 && port->dev) { + wakeup_mask = readb(up->port.membase + UART_WAKE_MASK_REG); + + spin_lock_irqsave(&port->lock, flags); + port->mctrl &= ~TIOCM_OUT2; + port->ops->set_mctrl(port, port->mctrl); + spin_unlock_irqrestore(&port->lock, flags); + + ret = (wakeup_mask & UART_WAKE_SRCS) != UART_WAKE_SRCS; + } + + writeb(UART_WAKE_SRCS, port->membase + UART_WAKE_REG); + mutex_unlock(&tport->mutex); + + return ret; +} + +static void pci1xxxx_port_resume(int line) +{ + struct uart_8250_port *up = serial8250_get_port(line); + struct uart_port *port = &up->port; + struct tty_port *tport = &port->state->port; + unsigned long flags; + + mutex_lock(&tport->mutex); + writeb(UART_BLOCK_SET_ACTIVE, port->membase + UART_ACTV_REG); + writeb(UART_WAKE_SRCS, port->membase + UART_WAKE_REG); + + if (port->suspended == 0) { + spin_lock_irqsave(&port->lock, flags); + port->mctrl |= TIOCM_OUT2; + port->ops->set_mctrl(port, port->mctrl); + spin_unlock_irqrestore(&port->lock, flags); + } + mutex_unlock(&tport->mutex); +} + +static int pci1xxxx_suspend(struct device *dev) +{ + struct pci1xxxx_8250 *priv = dev_get_drvdata(dev); + struct pci_dev *pcidev = to_pci_dev(dev); + bool wakeup = false; + unsigned int data; + void __iomem *p; + int i; + + for (i = 0; i < priv->nr; i++) { + if (priv->line[i] >= 0) { + serial8250_suspend_port(priv->line[i]); + wakeup |= pci1xxxx_port_suspend(priv->line[i]); + } + } + + p = pci_ioremap_bar(pcidev, 0); + if (!p) { + dev_err(dev, "remapping of bar 0 memory failed"); + return -ENOMEM; + } + + data = readl(p + UART_RESET_REG); + writel(data | UART_RESET_D3_RESET_DISABLE, p + UART_RESET_REG); + + if (wakeup) + writeb(UART_PCI_CTRL_D3_CLK_ENABLE, p + UART_PCI_CTRL_REG); + + iounmap(p); + device_set_wakeup_enable(dev, true); + pci_wake_from_d3(pcidev, true); + + return 0; +} + +static int pci1xxxx_resume(struct device *dev) +{ + struct pci1xxxx_8250 *priv = dev_get_drvdata(dev); + struct pci_dev *pcidev = to_pci_dev(dev); + unsigned int data; + void __iomem *p; + int i; + + p = pci_ioremap_bar(pcidev, 0); + if (!p) { + dev_err(dev, "remapping of bar 0 memory failed"); + return -ENOMEM; + } + + data = readl(p + UART_RESET_REG); + writel(data & ~UART_RESET_D3_RESET_DISABLE, p + UART_RESET_REG); + iounmap(p); + + for (i = 0; i < priv->nr; i++) { + if (priv->line[i] >= 0) { + pci1xxxx_port_resume(priv->line[i]); + serial8250_resume_port(priv->line[i]); + } + } + + return 0; +} + static int pci1xxxx_setup(struct pci_dev *pdev, struct uart_8250_port *port, int port_idx) { @@ -352,6 +462,8 @@ static void pci1xxxx_serial_remove(struct pci_dev *dev) pci_iounmap(dev, priv->membase); } +static DEFINE_SIMPLE_DEV_PM_OPS(pci1xxxx_pm_ops, pci1xxxx_suspend, pci1xxxx_resume); + static const struct pci_device_id pci1xxxx_pci_tbl[] = { { PCI_VDEVICE(EFAR, PCI_DEVICE_ID_EFAR_PCI11010) }, { PCI_VDEVICE(EFAR, PCI_DEVICE_ID_EFAR_PCI11101) }, @@ -366,6 +478,9 @@ static struct pci_driver pci1xxxx_pci_driver = { .name = "pci1xxxx serial", .probe = pci1xxxx_serial_probe, .remove = pci1xxxx_serial_remove, + .driver = { + .pm = pm_sleep_ptr(&pci1xxxx_pm_ops), + }, .id_table = pci1xxxx_pci_tbl, }; module_pci_driver(pci1xxxx_pci_driver); -- cgit v1.2.3