Merge tag 'tty-4.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial fixes from Greg KH:
 "Here are two tty serial driver fixes for 4.13-rc5. One is a revert of
  a -rc1 patch that turned out to not be a good idea, and the other is a
  fix for the pl011 serial driver.

  Both have been in linux-next with no reported issues"

* tag 'tty-4.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  Revert "serial: Delete dead code for CIR serial ports"
  tty: pl011: fix initialization order of QDF2400 E44

diff --git a/drivers/acpi/spcr.c b/drivers/acpi/spcr.c
index 4ac3e06b41d846440d35079dfa54885111eec0df..98aa8c808a3346dc559e2f419ae4378dec075ffc 100644 (file)
--- a/drivers/acpi/spcr.c
+++ b/drivers/acpi/spcr.c
@@ -16,6 +16,16 @@
 #include <linux/kernel.h>
 #include <linux/serial_core.h>
 
+/*
+ * Erratum 44 for QDF2432v1 and QDF2400v1 SoCs describes the BUSY bit as
+ * occasionally getting stuck as 1. To avoid the potential for a hang, check
+ * TXFE == 0 instead of BUSY == 1. This may not be suitable for all UART
+ * implementations, so only do so if an affected platform is detected in
+ * parse_spcr().
+ */
+bool qdf2400_e44_present;
+EXPORT_SYMBOL(qdf2400_e44_present);
+
 /*
  * Some Qualcomm Datacenter Technologies SoCs have a defective UART BUSY bit.
  * Detect them by examining the OEM fields in the SPCR header, similiar to PCI
@@ -147,8 +157,30 @@ int __init parse_spcr(bool earlycon)
                goto done;
        }
 
-       if (qdf2400_erratum_44_present(&table->header))
-               uart = "qdf2400_e44";
+       /*
+        * If the E44 erratum is required, then we need to tell the pl011
+        * driver to implement the work-around.
+        *
+        * The global variable is used by the probe function when it
+        * creates the UARTs, whether or not they're used as a console.
+        *
+        * If the user specifies "traditional" earlycon, the qdf2400_e44
+        * console name matches the EARLYCON_DECLARE() statement, and
+        * SPCR is not used.  Parameter "earlycon" is false.
+        *
+        * If the user specifies "SPCR" earlycon, then we need to update
+        * the console name so that it also says "qdf2400_e44".  Parameter
+        * "earlycon" is true.
+        *
+        * For consistency, if we change the console name, then we do it
+        * for everyone, not just earlycon.
+        */
+       if (qdf2400_erratum_44_present(&table->header)) {
+               qdf2400_e44_present = true;
+               if (earlycon)
+                       uart = "qdf2400_e44";
+       }
+
        if (xgene_8250_erratum_present(table))
                iotype = "mmio32";
 

diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
index b5def356af63b70e3ebc2e23a48da0753e41b47e..1aab3010fbfae76e2c25cb60085f21051a1f24cf 100644 (file)
--- a/drivers/tty/serial/8250/8250_core.c
+++ b/drivers/tty/serial/8250/8250_core.c
@@ -1043,13 +1043,24 @@ int serial8250_register_8250_port(struct uart_8250_port *up)
                if (up->dl_write)
                        uart->dl_write = up->dl_write;
 
-               if (serial8250_isa_config != NULL)
-                       serial8250_isa_config(0, &uart->port,
-                                       &uart->capabilities);
+               if (uart->port.type != PORT_8250_CIR) {
+                       if (serial8250_isa_config != NULL)
+                               serial8250_isa_config(0, &uart->port,
+                                               &uart->capabilities);
+
+                       ret = uart_add_one_port(&serial8250_reg,
+                                               &uart->port);
+                       if (ret == 0)
+                               ret = uart->port.line;
+               } else {
+                       dev_info(uart->port.dev,
+                               "skipping CIR port at 0x%lx / 0x%llx, IRQ %d\n",
+                               uart->port.iobase,
+                               (unsigned long long)uart->port.mapbase,
+                               uart->port.irq);
 
-               ret = uart_add_one_port(&serial8250_reg, &uart->port);
-               if (ret == 0)
-                       ret = uart->port.line;
+                       ret = 0;
+               }
        }
        mutex_unlock(&serial_mutex);
 

diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 8a857bb34fbb26c6d60784d3fe7576730a9aa5b3..1888d168a41c87c605962da2605df8ab1c02bd20 100644 (file)
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -142,15 +142,7 @@ static struct vendor_data vendor_sbsa = {
        .fixed_options          = true,
 };
 
-/*
- * Erratum 44 for QDF2432v1 and QDF2400v1 SoCs describes the BUSY bit as
- * occasionally getting stuck as 1. To avoid the potential for a hang, check
- * TXFE == 0 instead of BUSY == 1. This may not be suitable for all UART
- * implementations, so only do so if an affected platform is detected in
- * parse_spcr().
- */
-static bool qdf2400_e44_present = false;
-
+#ifdef CONFIG_ACPI_SPCR_TABLE
 static struct vendor_data vendor_qdt_qdf2400_e44 = {
        .reg_offset             = pl011_std_offsets,
        .fr_busy                = UART011_FR_TXFE,
@@ -165,6 +157,7 @@ static struct vendor_data vendor_qdt_qdf2400_e44 = {
        .always_enabled         = true,
        .fixed_options          = true,
 };
+#endif
 
 static u16 pl011_st_offsets[REG_ARRAY_SIZE] = {
        [REG_DR] = UART01x_DR,
@@ -2375,12 +2368,14 @@ static int __init pl011_console_match(struct console *co, char *name, int idx,
        resource_size_t addr;
        int i;
 
-       if (strcmp(name, "qdf2400_e44") == 0) {
-               pr_info_once("UART: Working around QDF2400 SoC erratum 44");
-               qdf2400_e44_present = true;
-       } else if (strcmp(name, "pl011") != 0) {
+       /*
+        * Systems affected by the Qualcomm Technologies QDF2400 E44 erratum
+        * have a distinct console name, so make sure we check for that.
+        * The actual implementation of the erratum occurs in the probe
+        * function.
+        */
+       if ((strcmp(name, "qdf2400_e44") != 0) && (strcmp(name, "pl011") != 0))
                return -ENODEV;
-       }
 
        if (uart_parse_earlycon(options, &iotype, &addr, &options))
                return -ENODEV;
@@ -2734,11 +2729,17 @@ static int sbsa_uart_probe(struct platform_device *pdev)
        }
        uap->port.irq   = ret;
 
-       uap->reg_offset = vendor_sbsa.reg_offset;
-       uap->vendor     = qdf2400_e44_present ?
-                                       &vendor_qdt_qdf2400_e44 : &vendor_sbsa;
+#ifdef CONFIG_ACPI_SPCR_TABLE
+       if (qdf2400_e44_present) {
+               dev_info(&pdev->dev, "working around QDF2400 SoC erratum 44\n");
+               uap->vendor = &vendor_qdt_qdf2400_e44;
+       } else
+#endif
+               uap->vendor = &vendor_sbsa;
+
+       uap->reg_offset = uap->vendor->reg_offset;
        uap->fifosize   = 32;
-       uap->port.iotype = vendor_sbsa.access_32b ? UPIO_MEM32 : UPIO_MEM;
+       uap->port.iotype = uap->vendor->access_32b ? UPIO_MEM32 : UPIO_MEM;
        uap->port.ops   = &sbsa_uart_pops;
        uap->fixed_baud = baudrate;
 

diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index c749eef1daa1557910ec81c5f296dc907f5ccab2..27b4b66152637fe38b82711f0fa66d6ce946f7d7 100644 (file)
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -1209,6 +1209,7 @@ static inline bool acpi_has_watchdog(void) { return false; }
 #endif
 
 #ifdef CONFIG_ACPI_SPCR_TABLE
+extern bool qdf2400_e44_present;
 int parse_spcr(bool earlycon);
 #else
 static inline int parse_spcr(bool earlycon) { return 0; }