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linux/include/misc/charlcd.h

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auxdisplay: charlcd: Extract character LCD core from misc/panel Extract the character LCD core from the Parallel port LCD/Keypad Panel driver in the misc subsystem, and convert it into a subdriver in the auxdisplay subsystem. This allows the character LCD core to be used by other drivers later. Compilation is controlled by its own Kconfig symbol CHARLCD, which is to be selected by its users, but can be enabled manually for compile-testing. All functions changed their prefix from "lcd_" to "charlcd_", and gained a "struct charlcd *" parameter to operate on a specific instance. While the driver API thus is ready to support multiple instances, the current limitation of a single display (/dev/lcd has a single misc minor assigned) is retained. No functional changes intended. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-10 15:15:17 +01:00
auxdisplay: charlcd: Add support for 4-bit interfaces In 4-bit mode, 8-bit commands and data are written using two raw writes to the data interface: high nibble first, low nibble last. This must be handled by the low-level driver. However, as we don't know in which mode (4-bit or 8-bit) nor 4-bit phase the LCD was left, initialization must always be handled using raw writes, and needs to configure the LCD for 8-bit mode first. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-10 15:15:18 +01:00
auxdisplay: charlcd: Extract character LCD core from misc/panel Extract the character LCD core from the Parallel port LCD/Keypad Panel driver in the misc subsystem, and convert it into a subdriver in the auxdisplay subsystem. This allows the character LCD core to be used by other drivers later. Compilation is controlled by its own Kconfig symbol CHARLCD, which is to be selected by its users, but can be enabled manually for compile-testing. All functions changed their prefix from "lcd_" to "charlcd_", and gained a "struct charlcd *" parameter to operate on a specific instance. While the driver API thus is ready to support multiple instances, the current limitation of a single display (/dev/lcd has a single misc minor assigned) is retained. No functional changes intended. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-10 15:15:17 +01:00
auxdisplay: charlcd: Add support for 4-bit interfaces In 4-bit mode, 8-bit commands and data are written using two raw writes to the data interface: high nibble first, low nibble last. This must be handled by the low-level driver. However, as we don't know in which mode (4-bit or 8-bit) nor 4-bit phase the LCD was left, initialization must always be handled using raw writes, and needs to configure the LCD for 8-bit mode first. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-10 15:15:18 +01:00
auxdisplay: charlcd: Extract character LCD core from misc/panel Extract the character LCD core from the Parallel port LCD/Keypad Panel driver in the misc subsystem, and convert it into a subdriver in the auxdisplay subsystem. This allows the character LCD core to be used by other drivers later. Compilation is controlled by its own Kconfig symbol CHARLCD, which is to be selected by its users, but can be enabled manually for compile-testing. All functions changed their prefix from "lcd_" to "charlcd_", and gained a "struct charlcd *" parameter to operate on a specific instance. While the driver API thus is ready to support multiple instances, the current limitation of a single display (/dev/lcd has a single misc minor assigned) is retained. No functional changes intended. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-10 15:15:17 +01:00
auxdisplay: charlcd: Introduce charlcd_free() helper The charlcd_free() is a counterpart to charlcd_alloc() and should be called symmetrically on tear down. Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
2019-03-12 16:44:30 +02:00
auxdisplay: charlcd: Extract character LCD core from misc/panel Extract the character LCD core from the Parallel port LCD/Keypad Panel driver in the misc subsystem, and convert it into a subdriver in the auxdisplay subsystem. This allows the character LCD core to be used by other drivers later. Compilation is controlled by its own Kconfig symbol CHARLCD, which is to be selected by its users, but can be enabled manually for compile-testing. All functions changed their prefix from "lcd_" to "charlcd_", and gained a "struct charlcd *" parameter to operate on a specific instance. While the driver API thus is ready to support multiple instances, the current limitation of a single display (/dev/lcd has a single misc minor assigned) is retained. No functional changes intended. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-10 15:15:17 +01:00