diff options
Diffstat (limited to 'drivers/media/v4l2-core/v4l2-dv-timings.c')
| -rw-r--r-- | drivers/media/v4l2-core/v4l2-dv-timings.c | 151 |
1 files changed, 151 insertions, 0 deletions
diff --git a/drivers/media/v4l2-core/v4l2-dv-timings.c b/drivers/media/v4l2-core/v4l2-dv-timings.c index 8f52353b0881..b4e50c5509b7 100644 --- a/drivers/media/v4l2-core/v4l2-dv-timings.c +++ b/drivers/media/v4l2-core/v4l2-dv-timings.c @@ -15,6 +15,7 @@ #include <media/v4l2-dv-timings.h> #include <linux/math64.h> #include <linux/hdmi.h> +#include <media/cec.h> MODULE_AUTHOR("Hans Verkuil"); MODULE_DESCRIPTION("V4L2 DV Timings Helper Functions"); @@ -981,3 +982,153 @@ v4l2_hdmi_rx_colorimetry(const struct hdmi_avi_infoframe *avi, return c; } EXPORT_SYMBOL_GPL(v4l2_hdmi_rx_colorimetry); + +/** + * v4l2_get_edid_phys_addr() - find and return the physical address + * + * @edid: pointer to the EDID data + * @size: size in bytes of the EDID data + * @offset: If not %NULL then the location of the physical address + * bytes in the EDID will be returned here. This is set to 0 + * if there is no physical address found. + * + * Return: the physical address or CEC_PHYS_ADDR_INVALID if there is none. + */ +u16 v4l2_get_edid_phys_addr(const u8 *edid, unsigned int size, + unsigned int *offset) +{ + unsigned int loc = cec_get_edid_spa_location(edid, size); + + if (offset) + *offset = loc; + if (loc == 0) + return CEC_PHYS_ADDR_INVALID; + return (edid[loc] << 8) | edid[loc + 1]; +} +EXPORT_SYMBOL_GPL(v4l2_get_edid_phys_addr); + +/** + * v4l2_set_edid_phys_addr() - find and set the physical address + * + * @edid: pointer to the EDID data + * @size: size in bytes of the EDID data + * @phys_addr: the new physical address + * + * This function finds the location of the physical address in the EDID + * and fills in the given physical address and updates the checksum + * at the end of the EDID block. It does nothing if the EDID doesn't + * contain a physical address. + */ +void v4l2_set_edid_phys_addr(u8 *edid, unsigned int size, u16 phys_addr) +{ + unsigned int loc = cec_get_edid_spa_location(edid, size); + u8 sum = 0; + unsigned int i; + + if (loc == 0) + return; + edid[loc] = phys_addr >> 8; + edid[loc + 1] = phys_addr & 0xff; + loc &= ~0x7f; + + /* update the checksum */ + for (i = loc; i < loc + 127; i++) + sum += edid[i]; + edid[i] = 256 - sum; +} +EXPORT_SYMBOL_GPL(v4l2_set_edid_phys_addr); + +/** + * v4l2_phys_addr_for_input() - calculate the PA for an input + * + * @phys_addr: the physical address of the parent + * @input: the number of the input port, must be between 1 and 15 + * + * This function calculates a new physical address based on the input + * port number. For example: + * + * PA = 0.0.0.0 and input = 2 becomes 2.0.0.0 + * + * PA = 3.0.0.0 and input = 1 becomes 3.1.0.0 + * + * PA = 3.2.1.0 and input = 5 becomes 3.2.1.5 + * + * PA = 3.2.1.3 and input = 5 becomes f.f.f.f since it maxed out the depth. + * + * Return: the new physical address or CEC_PHYS_ADDR_INVALID. + */ +u16 v4l2_phys_addr_for_input(u16 phys_addr, u8 input) +{ + /* Check if input is sane */ + if (WARN_ON(input == 0 || input > 0xf)) + return CEC_PHYS_ADDR_INVALID; + + if (phys_addr == 0) + return input << 12; + + if ((phys_addr & 0x0fff) == 0) + return phys_addr | (input << 8); + + if ((phys_addr & 0x00ff) == 0) + return phys_addr | (input << 4); + + if ((phys_addr & 0x000f) == 0) + return phys_addr | input; + + /* + * All nibbles are used so no valid physical addresses can be assigned + * to the input. + */ + return CEC_PHYS_ADDR_INVALID; +} +EXPORT_SYMBOL_GPL(v4l2_phys_addr_for_input); + +/** + * v4l2_phys_addr_validate() - validate a physical address from an EDID + * + * @phys_addr: the physical address to validate + * @parent: if not %NULL, then this is filled with the parents PA. + * @port: if not %NULL, then this is filled with the input port. + * + * This validates a physical address as read from an EDID. If the + * PA is invalid (such as 1.0.1.0 since '0' is only allowed at the end), + * then it will return -EINVAL. + * + * The parent PA is passed into %parent and the input port is passed into + * %port. For example: + * + * PA = 0.0.0.0: has parent 0.0.0.0 and input port 0. + * + * PA = 1.0.0.0: has parent 0.0.0.0 and input port 1. + * + * PA = 3.2.0.0: has parent 3.0.0.0 and input port 2. + * + * PA = f.f.f.f: has parent f.f.f.f and input port 0. + * + * Return: 0 if the PA is valid, -EINVAL if not. + */ +int v4l2_phys_addr_validate(u16 phys_addr, u16 *parent, u16 *port) +{ + int i; + + if (parent) + *parent = phys_addr; + if (port) + *port = 0; + if (phys_addr == CEC_PHYS_ADDR_INVALID) + return 0; + for (i = 0; i < 16; i += 4) + if (phys_addr & (0xf << i)) + break; + if (i == 16) + return 0; + if (parent) + *parent = phys_addr & (0xfff0 << i); + if (port) + *port = (phys_addr >> i) & 0xf; + for (i += 4; i < 16; i += 4) + if ((phys_addr & (0xf << i)) == 0) + return -EINVAL; + return 0; +} +EXPORT_SYMBOL_GPL(v4l2_phys_addr_validate); |