diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-tty | 3 | ||||
| -rw-r--r-- | Documentation/PCI/MSI-HOWTO.txt | 119 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/arm/omap/omap.txt | 2 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/clock/renesas,cpg-mstp-clocks.txt | 4 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/dma/fsl-imx-sdma.txt | 16 |
5 files changed, 123 insertions, 21 deletions
diff --git a/Documentation/ABI/testing/sysfs-tty b/Documentation/ABI/testing/sysfs-tty index a2ccec35ffce..ad22fb0ee765 100644 --- a/Documentation/ABI/testing/sysfs-tty +++ b/Documentation/ABI/testing/sysfs-tty @@ -3,8 +3,7 @@ Date: Nov 2010 Contact: Kay Sievers <kay.sievers@vrfy.org> Description: Shows the list of currently configured - tty devices used for the console, - like 'tty1 ttyS0'. + console devices, like 'tty1 ttyS0'. The last entry in the file is the active device connected to /dev/console. The file supports poll() to detect virtual diff --git a/Documentation/PCI/MSI-HOWTO.txt b/Documentation/PCI/MSI-HOWTO.txt index a8d01005f480..10a93696e55a 100644 --- a/Documentation/PCI/MSI-HOWTO.txt +++ b/Documentation/PCI/MSI-HOWTO.txt @@ -82,7 +82,19 @@ Most of the hard work is done for the driver in the PCI layer. It simply has to request that the PCI layer set up the MSI capability for this device. -4.2.1 pci_enable_msi_range +4.2.1 pci_enable_msi + +int pci_enable_msi(struct pci_dev *dev) + +A successful call allocates ONE interrupt to the device, regardless +of how many MSIs the device supports. The device is switched from +pin-based interrupt mode to MSI mode. The dev->irq number is changed +to a new number which represents the message signaled interrupt; +consequently, this function should be called before the driver calls +request_irq(), because an MSI is delivered via a vector that is +different from the vector of a pin-based interrupt. + +4.2.2 pci_enable_msi_range int pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec) @@ -147,6 +159,11 @@ static int foo_driver_enable_msi(struct pci_dev *pdev, int nvec) return pci_enable_msi_range(pdev, nvec, nvec); } +Note, unlike pci_enable_msi_exact() function, which could be also used to +enable a particular number of MSI-X interrupts, pci_enable_msi_range() +returns either a negative errno or 'nvec' (not negative errno or 0 - as +pci_enable_msi_exact() does). + 4.2.1.3 Single MSI mode The most notorious example of the request type described above is @@ -158,7 +175,27 @@ static int foo_driver_enable_single_msi(struct pci_dev *pdev) return pci_enable_msi_range(pdev, 1, 1); } -4.2.2 pci_disable_msi +Note, unlike pci_enable_msi() function, which could be also used to +enable the single MSI mode, pci_enable_msi_range() returns either a +negative errno or 1 (not negative errno or 0 - as pci_enable_msi() +does). + +4.2.3 pci_enable_msi_exact + +int pci_enable_msi_exact(struct pci_dev *dev, int nvec) + +This variation on pci_enable_msi_range() call allows a device driver to +request exactly 'nvec' MSIs. + +If this function returns a negative number, it indicates an error and +the driver should not attempt to request any more MSI interrupts for +this device. + +By contrast with pci_enable_msi_range() function, pci_enable_msi_exact() +returns zero in case of success, which indicates MSI interrupts have been +successfully allocated. + +4.2.4 pci_disable_msi void pci_disable_msi(struct pci_dev *dev) @@ -172,7 +209,7 @@ on any interrupt for which it previously called request_irq(). Failure to do so results in a BUG_ON(), leaving the device with MSI enabled and thus leaking its vector. -4.2.3 pci_msi_vec_count +4.2.4 pci_msi_vec_count int pci_msi_vec_count(struct pci_dev *dev) @@ -257,8 +294,8 @@ possible, likely up to the limit returned by pci_msix_vec_count() function: static int foo_driver_enable_msix(struct foo_adapter *adapter, int nvec) { - return pci_enable_msi_range(adapter->pdev, adapter->msix_entries, - 1, nvec); + return pci_enable_msix_range(adapter->pdev, adapter->msix_entries, + 1, nvec); } Note the value of 'minvec' parameter is 1. As 'minvec' is inclusive, @@ -269,8 +306,8 @@ In this case the function could look like this: static int foo_driver_enable_msix(struct foo_adapter *adapter, int nvec) { - return pci_enable_msi_range(adapter->pdev, adapter->msix_entries, - FOO_DRIVER_MINIMUM_NVEC, nvec); + return pci_enable_msix_range(adapter->pdev, adapter->msix_entries, + FOO_DRIVER_MINIMUM_NVEC, nvec); } 4.3.1.2 Exact number of MSI-X interrupts @@ -282,10 +319,15 @@ parameters: static int foo_driver_enable_msix(struct foo_adapter *adapter, int nvec) { - return pci_enable_msi_range(adapter->pdev, adapter->msix_entries, - nvec, nvec); + return pci_enable_msix_range(adapter->pdev, adapter->msix_entries, + nvec, nvec); } +Note, unlike pci_enable_msix_exact() function, which could be also used to +enable a particular number of MSI-X interrupts, pci_enable_msix_range() +returns either a negative errno or 'nvec' (not negative errno or 0 - as +pci_enable_msix_exact() does). + 4.3.1.3 Specific requirements to the number of MSI-X interrupts As noted above, there could be devices that can not operate with just any @@ -332,7 +374,64 @@ Note how pci_enable_msix_range() return value is analized for a fallback - any error code other than -ENOSPC indicates a fatal error and should not be retried. -4.3.2 pci_disable_msix +4.3.2 pci_enable_msix_exact + +int pci_enable_msix_exact(struct pci_dev *dev, + struct msix_entry *entries, int nvec) + +This variation on pci_enable_msix_range() call allows a device driver to +request exactly 'nvec' MSI-Xs. + +If this function returns a negative number, it indicates an error and +the driver should not attempt to allocate any more MSI-X interrupts for +this device. + +By contrast with pci_enable_msix_range() function, pci_enable_msix_exact() +returns zero in case of success, which indicates MSI-X interrupts have been +successfully allocated. + +Another version of a routine that enables MSI-X mode for a device with +specific requirements described in chapter 4.3.1.3 might look like this: + +/* + * Assume 'minvec' and 'maxvec' are non-zero + */ +static int foo_driver_enable_msix(struct foo_adapter *adapter, + int minvec, int maxvec) +{ + int rc; + + minvec = roundup_pow_of_two(minvec); + maxvec = rounddown_pow_of_two(maxvec); + + if (minvec > maxvec) + return -ERANGE; + +retry: + rc = pci_enable_msix_exact(adapter->pdev, + adapter->msix_entries, maxvec); + + /* + * -ENOSPC is the only error code allowed to be analyzed + */ + if (rc == -ENOSPC) { + if (maxvec == 1) + return -ENOSPC; + + maxvec /= 2; + + if (minvec > maxvec) + return -ENOSPC; + + goto retry; + } else if (rc < 0) { + return rc; + } + + return maxvec; +} + +4.3.3 pci_disable_msix void pci_disable_msix(struct pci_dev *dev) diff --git a/Documentation/devicetree/bindings/arm/omap/omap.txt b/Documentation/devicetree/bindings/arm/omap/omap.txt index 34dc40cffdfd..af9b4a0d902b 100644 --- a/Documentation/devicetree/bindings/arm/omap/omap.txt +++ b/Documentation/devicetree/bindings/arm/omap/omap.txt @@ -91,7 +91,7 @@ Boards: compatible = "ti,omap3-beagle", "ti,omap3" - OMAP3 Tobi with Overo : Commercial expansion board with daughter board - compatible = "ti,omap3-tobi", "ti,omap3-overo", "ti,omap3" + compatible = "gumstix,omap3-overo-tobi", "gumstix,omap3-overo", "ti,omap3" - OMAP4 SDP : Software Development Board compatible = "ti,omap4-sdp", "ti,omap4430" diff --git a/Documentation/devicetree/bindings/clock/renesas,cpg-mstp-clocks.txt b/Documentation/devicetree/bindings/clock/renesas,cpg-mstp-clocks.txt index a6a352c2771e..5992dceec7af 100644 --- a/Documentation/devicetree/bindings/clock/renesas,cpg-mstp-clocks.txt +++ b/Documentation/devicetree/bindings/clock/renesas,cpg-mstp-clocks.txt @@ -21,9 +21,9 @@ Required Properties: must appear in the same order as the output clocks. - #clock-cells: Must be 1 - clock-output-names: The name of the clocks as free-form strings - - renesas,indices: Indices of the gate clocks into the group (0 to 31) + - renesas,clock-indices: Indices of the gate clocks into the group (0 to 31) -The clocks, clock-output-names and renesas,indices properties contain one +The clocks, clock-output-names and renesas,clock-indices properties contain one entry per gate clock. The MSTP groups are sparsely populated. Unimplemented gate clocks must not be declared. diff --git a/Documentation/devicetree/bindings/dma/fsl-imx-sdma.txt b/Documentation/devicetree/bindings/dma/fsl-imx-sdma.txt index 68b83ecc3850..ee9be9961524 100644 --- a/Documentation/devicetree/bindings/dma/fsl-imx-sdma.txt +++ b/Documentation/devicetree/bindings/dma/fsl-imx-sdma.txt @@ -1,12 +1,16 @@ * Freescale Smart Direct Memory Access (SDMA) Controller for i.MX Required properties: -- compatible : Should be "fsl,imx31-sdma", "fsl,imx31-to1-sdma", - "fsl,imx31-to2-sdma", "fsl,imx35-sdma", "fsl,imx35-to1-sdma", - "fsl,imx35-to2-sdma", "fsl,imx51-sdma", "fsl,imx53-sdma" or - "fsl,imx6q-sdma". The -to variants should be preferred since they - allow to determnine the correct ROM script addresses needed for - the driver to work without additional firmware. +- compatible : Should be one of + "fsl,imx25-sdma" + "fsl,imx31-sdma", "fsl,imx31-to1-sdma", "fsl,imx31-to2-sdma" + "fsl,imx35-sdma", "fsl,imx35-to1-sdma", "fsl,imx35-to2-sdma" + "fsl,imx51-sdma" + "fsl,imx53-sdma" + "fsl,imx6q-sdma" + The -to variants should be preferred since they allow to determnine the + correct ROM script addresses needed for the driver to work without additional + firmware. - reg : Should contain SDMA registers location and length - interrupts : Should contain SDMA interrupt - #dma-cells : Must be <3>. |